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  • Psettodoidei (fish suborder)

    pleuronectiform: Annotated classification: Suborder Psettodoidei The least-specialized (most primitive) flatfish. Spines present in dorsal, anal, and pelvic fins; dorsal fin not extending onto head; eyes on either right (dextral) or left (sinistral) side; maxillary (upper jaw) bone with well-developed supplemental bone; vertebrae 24–25 (10 precaudal, 14–15 caudal). Family Psettodidae…

  • Pseudacris (amphibian)

    Chorus frog, (Pseudacris), any of several species of tree frogs belonging to the family Hylidae. Chorus frogs are found in North America from Canada to the southern United States and the northern reaches of Mexico. They are predominantly terrestrial and live in thick herbaceous vegetation and low

  • Pseudacris crucifer (amphibian)

    Spring peeper, (species Pseudacris crucifer), small tree frog (family Hylidae) found in woodland areas in the eastern United States and Canada. Outside of the breeding season, when it may be found in ephemeral woodland ponds, it is seldom seen. The spring peeper, with its high, whistling call, is

  • Pseudacris ocularis (amphibian)

    chorus frog: …115 inches) long, but the little grass frog (P. ocularis) reaches a maximum of 1.9 cm (34 inch), and Strecker’s chorus frog (P. streckeri) may grow to 4.5 cm (145 inches).

  • Pseudacris streckeri (amphibian)

    chorus frog: 9 cm (34 inch), and Strecker’s chorus frog (P. streckeri) may grow to 4.5 cm (145 inches).

  • Pseudagenia (wasp genus)

    spider wasp: …of the North American genus Pseudagenia construct cells of mud under bark or among stones. Some species construct the nest before capturing the spider; others capture the spider first, then set it aside until the nest is completed. A single spider and a single egg are placed in the nest.…

  • Pseudalopex (genus of mammals)

    South American fox, (genus Lycalopex), any of six South American carnivores of the dog family (Canidae). Although these canines are not actually foxes, they resemble true foxes. In general, South American foxes are long-haired, rather grayish animals that grow to about 0.5–1 metre (1.6–3.3 feet) in

  • pseudanthium (plant anatomy)

    Cyperaceae: Evolution and classification: The subfamily Mapanioideae has a pseudanthium, or false flower, composed of a single terminal female flower surrounded by a number of naked stamens, each of which is subtended by a bract with the lowest two stamens situated opposite each other. In the genus Hypolytrum, only the two opposite stamens and…

  • Pseudaria (work by Euclid)

    Euclid: Other writings: The purpose of the Pseudaria (“Fallacies”), says Proclus, was to distinguish and to warn beginners against different types of fallacies to which they might be susceptible in geometrical reasoning. According to Pappus, the Porisms (“Corollaries”), in three books, contained 171 propositions. Michel Chasles (1793–1880) conjectured that the work contained…

  • pseudarthrosis (pathology)

    bone disease: Fractures: …results in a false joint—pseudarthrosis—characterized by pain and motion at the fracture site. Healing may be achieved by immobilization with or without internal fixation and by transplantation of bone to bridge the defect.

  • Pseudechis porphyriacus (snake)

    black snake: …two species of black snakes, Pseudechis porphyriacus and P. guttatus. P. porphyriacus is a small-headed member of the cobra family, Elapidae. It is blue-black with a red belly, and its average length is about 1.5 metres (5 feet). If annoyed, it expands its neck, cobra fashion. Its venom—more hemorrhagic than…

  • Pseudemys scripta (reptile)

    sound reception: Turtles: …that turtles of the species Pseudemys scripta, trained to withdraw their head, respond to sound over the low-frequency range, with the greatest sensitivity in the region of 200 to 640 hertz. This result is in close agreement with electrophysiological observations in which it has been found that impulses could be…

  • pseudencephaly (pathology)

    malformation: Somatic characters: …variant of this type is pseudencephaly, in which the whole brain is everted and rests upon the top of the cranium like a wig.

  • pseudepigrapha (literature)

    Pseudepigrapha, in biblical literature, a work affecting biblical style and usually spuriously attributing authorship to some biblical character. Pseudepigrapha are not included in any canon. See

  • pseudergate (zoology)

    termite: Workers and soldiers: …out by immature individuals called pseudo-workers or pseudergates, which may molt without much change in size.

  • Pseudidae (amphibian family)

    Anura: Annotated classification: Family Pseudidae No fossil record; 8 presacral vertebrae; sacral diapophyses round; pectoral girdle arciferal; intercalary cartilages present, ossified; omosternum present; Bidder’s organ absent; maxillary teeth present; aquatic larvae (which grow to a much larger size than the adult); South America east of Andes; 2 genera, 3…

  • Pseudo-Ambrosius (early Christian writer)

    Ambrosiaster, the name given to the author of a commentary on St. Paul’s letters in the New Testament, long attributed to St. Ambrose (died 397), bishop of Milan. The work is valuable for the criticism of the Latin text of the New Testament. In 1527 Erasmus expressed doubts that the work was

  • Pseudo-Cyprianus (Irish writer)

    mirror for princes: …and vices by the so-called Pseudo-Cyprianus, an otherwise unknown Irish writer, established a clear link between moral and political authority and explained how the personal moral shortcomings of individual rulers influenced the fortunes of their people—an explanation that assigned responsibility to rulers for floods, famines, and foreign invasions (as divine…

  • Pseudo-Demetrius (Russian pretenders)

    False Dmitry, any of three different pretenders to the Muscovite throne who, during the Time of Troubles (1598–1613), claimed to be Dmitry Ivanovich, the son of Tsar Ivan IV the Terrible (reigned 1533–84) who had died mysteriously in 1591 while still a child. After Fyodor I (reigned 1584–98), the

  • Pseudo-Denis the Areopagite (Syrian author)

    Pseudo-Dionysius The Areopagite , probably a Syrian monk who, known only by his pseudonym, wrote a series of Greek treatises and letters for the purpose of uniting Neoplatonic philosophy with Christian theology and mystical experience. These writings established a definite Neoplatonic trend in a

  • Pseudo-Dionysius the Areopagite (Syrian author)

    Pseudo-Dionysius The Areopagite , probably a Syrian monk who, known only by his pseudonym, wrote a series of Greek treatises and letters for the purpose of uniting Neoplatonic philosophy with Christian theology and mystical experience. These writings established a definite Neoplatonic trend in a

  • pseudo-event

    Pseudo-event, an event produced by a communicator with the sole purpose of generating media attention and publicity. These events lack real news value but still become the subject of media coverage. In short, pseudo-events are a public relations tactic. The term pseudo-event was coined by American

  • Pseudo-Ezekiel and the Original Prophecy (work by Torrey)

    Charles Cutler Torrey: His Pseudo-Ezekiel and the Original Prophecy (1930) presents his theory that the canonical book of Ezekiel is a revision of a 3rd-century pseudepigraphon. In The Translations Made from the Original Aramaic Gospels (1912), The Four Gospels: A New Translation (1933), and Our Translated Gospels (1936), Torrey…

  • pseudo-H zone (physiology)

    muscle: Cross bridges: …bridges and is called the pseudo-H zone. In the centre of the A band is a narrow, darkly stained region called the M band, in which occur fine bridges between the thick filaments. These bridges differ from the cross bridges between the thick and thin filaments and are in fact…

  • pseudo-hypertropic muscular dystrophy

    muscle disease: The muscular dystrophies: …that are relatively benign, the Duchenne type, which predominately affects boys, is severe. It causes difficulty in walking at about the age of four years, loss of the ability to walk at about the age of 11, and death before the age of 20, usually because of respiratory failure or…

  • Pseudo-Isidore, Decretals of (religious literature)

    False Decretals, a 9th-century collection of ecclesiastical legislation containing some forged documents. The principal aim of the forgers was to free the Roman Catholic church from interference by the state and to maintain the independence of the bishops against the encroachments of the

  • Pseudo-Longinus (Greek literary critic)

    Longinus, name sometimes assigned to the author of On the Sublime (Greek Peri Hypsous), one of the great seminal works of literary criticism. The earliest surviving manuscript, from the 10th century, first printed in 1554, ascribes it to Dionysius Longinus. Later it was noticed that the index to

  • Pseudo-Martyr (work by Donne)

    John Donne: Prose: ” Donne’s Pseudo-Martyr, published in 1610, attacks the recusants’ unwillingness to swear the oath of allegiance to the king, which Roman Catholics were required to do after the Gunpowder Plot (1605). The treatise so pleased James I that he had Oxford confer an honorary master of arts…

  • Pseudo-Methodius (author)

    Christianity: The Middle Ages: …the Syriac work of the Pseudo-Methodius, who wrote in response to the expansion of Islam into Christian territories. Translated into Greek and Latin, Pseudo-Methodius provided the basis for further reworking of the legend in the 10th and 11th centuries by writers in the Latin West. The legend itself describes the…

  • Pseudo-Scotus (medieval author)

    history of logic: Developments in the 13th and early 14th centuries: …as the works of “the Pseudo-Scotus,” although they may not all be by the same author.

  • pseudo-worker (zoology)

    termite: Workers and soldiers: …out by immature individuals called pseudo-workers or pseudergates, which may molt without much change in size.

  • Pseudobornia ursina (fossil plant)

    Equisetopsida: Annotated classification: …with a single extinct species, Pseudobornia ursina; 15 to 20 metres (50 to 65 feet) tall. †Order Sphenophyllales Extinct scrambling or vinelike understory plants, 1 metre (3 feet) tall, with small, wedge-shape leaves; 2 families: Sphenophyllaceae and Cheirostrobaceae. Order Equisetales

  • Pseudoborniaceae (fossil plant family)

    Equisetopsida: Annotated classification: Pseudoborniales One family, Pseudoborniaceae, with a single extinct species, Pseudobornia ursina; 15 to 20 metres (50 to 65 feet) tall. †Order Sphenophyllales Extinct scrambling or vinelike understory plants, 1 metre (3 feet) tall, with small, wedge-shape leaves; 2 families: Sphenophyllaceae and Cheirostrobaceae

  • Pseudoborniales (fossil plant order)

    Equisetopsida: Annotated classification: †Order Pseudoborniales One family, Pseudoborniaceae, with a single extinct species, Pseudobornia ursina; 15 to 20 metres (50 to 65 feet) tall. †Order Sphenophyllales Extinct scrambling or vinelike understory plants, 1 metre (3 feet) tall, with small, wedge-shape leaves; 2 families:

  • Pseudobranchus (amphibian)

    siren: The dwarf siren (Pseudobranchus striatus) lives in waterways from southern South Carolina to northern Florida, and the narrow-striped dwarf siren (P. axanthus) inhabits similar habitat across peninsular Florida. Adult dwarf sirens are about 10–22 cm (3.9–8.7 inches) long.

  • pseudobulb (plant anatomy)

    Corm, vertical, fleshy, underground stem that acts as a food-storage structure in certain seed plants. It bears membranous or scaly leaves and buds, and, unlike in bulbs, these do not appear as visible rings when the corm is cut in half. Corms have a fibrous covering known as a tunic, and the roots

  • Pseudocarchariidae (shark family)

    chondrichthyan: Annotated classification: Family Pseudocarchariidae (crocodile sharks) Large eyes for hunting in deep water. Feeds on fish and squid. To about 1 metre (about 3 feet) long. 1 species (Pseudocarcharias kamoharai), worldwide in offshore tropical waters. Miocene to present. Family Lamnidae (salmon sharks, mako sharks,

  • Pseudocarcinus gigas (crustacean)

    crab: Distribution and variety: …Japan (Macrocheira kaempferi) and the Tasmanian crab (Pseudocarcinus gigas) are two of the largest known crustaceans. The former may span nearly 4 metres (12 feet) from tip to tip of its outstretched legs. The Tasmanian crab, which may weigh well over 9 kg (20 pounds), has much shorter, stouter claws;…

  • pseudocarp (botany)

    fruit: Types of fruits: …the apple or strawberry, an accessory fruit results.

  • pseudocereal (food)

    amaranth: …seeds, which are a nutritious pseudocereal (nongrass seeds used like cereal grains). A number of species, including love-lies-bleeding (Amaranthus caudatus), prince’s feather (A. hypochondriacus), and Joseph’s coat (A. tricolor), are common garden ornamentals. Several species are considered weeds.

  • Pseudochactidae (scorpion family)

    scorpion: Annotated classification: Family Pseudochactidae 1 species of Central Asia; first described in 1998. Assorted Referencesmajor referenceannotated classification

  • Pseudocheiridae (marsupial family)

    marsupial: Classification: Family Pseudocheiridae (ringtail possums and greater glider) 15 or so species in 5 genera. Arboreal prehensile-tailed marsupials with complex ridged teeth. Family Petauridae (gliders and striped possums) 10 or so species in 3 genera. Terrestrial and arboreal. 1st and 2nd digits of

  • Pseudocheirus peregrinus (marsupial)

    temperate forest: Fauna: …and opossums such as the common ringtail (Pseudocheirus peregrinus), which nests in holes, and the well-known koala (Phascolarctos cinerea), which is free-living and feeds mainly or entirely on young tree foliage.

  • Pseudochelidon eurystomina (bird)

    martin: The African river martin (Pseudochelidon eurystomina) of the Congo River is black, with red eyes and bill; it is sometimes placed in a separate family, Pseudochelidonidae. The so-called bee-martin, or bee bird, is not a martin but a kingbird.

  • Pseudochromidae (fish family)

    perciform: Annotated classification: Families Pseudochromidae, Grammatidae, and Plesiopidae Quite similar, small, darkly colourful, rather secretive coral-reef basslike fishes of tropical Indo-Pacific and Caribbean seas. An interesting specialization of numerous species is the presence of multiple horizontal, interrupted lateral lines on trunk: 1 along the back, 1 along the side,…

  • Pseudococcidae (insect)

    Mealybug, (family Pseudococcidae), any of a group of small sap-sucking insects (order Homoptera) that are worldwide in distribution and attack citrus trees and ornamental plants, especially in interior plantscapes and greenhouses. Observed most frequently is the ovoid, sluggish mature female, about

  • Pseudococcus calceolariae (insect)

    biological control: …include the destruction of the citrophilus mealybug in California by two parasitic species of chalcid wasps imported from Australia, Coccophagus gurneyi and Tetracnemus pretiosus; the effective predation of an Australian ladybird beetle, or vedalia beetle (Rodolia cardinalis), on the cottony cushion scale in California; the limiting of the proliferation of…

  • pseudocoel (anatomy)

    circulatory system: General features of circulation: …a fluid-filled cavity, called the pseudocoelom, that arises from an embryonic cavity and contains the internal organs free within it. All other eumetazoans have a body cavity, the coelom, which originates as a cavity in the embryonic mesoderm. Mesoderm lines the coelom and forms the peritoneum, which also surrounds and…

  • pseudocoelomate (biology)

    animal: Pseudocoelomates, or aschelminths: The pseudocoelomates include the nematodes, rotifers, gastrotrichs, and introverts. Some members of some other phyla are also, strictly speaking, pseudocoelomate. These four phyla of tiny body size (many species no larger than the bigger protozoans) are placed together in part because they…

  • pseudocopulation (biology)

    Pseudocopulation, the action of a male insect, such as a bee, wasp, or fly, that tries to mate with a flower whose parts resemble those of a female insect of the same species as the male. Masses of pollen become attached to the male insect during this process and are transferred to the next flower

  • pseudoculus (anatomy)

    pauropod: …a pair of vibration-sensitive organs (pseudoculi) instead of eyes. The body consists of 11 partially fused segments from which project nine pairs of legs, the first pair reduced and five jointed. Respiration occurs at the body surface in pauropods. Their reproductive system is equally simple; as in millipedes, the reproductive…

  • pseudocyesis

    False pregnancy, disorder that may mimic many of the effects of pregnancy, including enlargement of the uterus, cessation of menstruation, morning sickness, and even labour pains at term. The cause may be physical—the growth of a tumour or hydatidiform mole in the uterus—or

  • Pseudodoxia Epidemica, or, Enquiries into Very many received Tenets, and commonly presumed truths (work by Browne)

    Sir Thomas Browne: …his second and larger work, Pseudodoxia Epidemica, or, Enquiries into Very many received Tenets, and commonly presumed truths (1646), often known as Browne’s Vulgar Errors. In it he tried to correct many popular beliefs and superstitions. In 1658 he published his third book, two treatises on antiquarian subjects, Hydriotaphia, Urne-Buriall,…

  • pseudofeces (biology)

    bivalve: Internal features: …a mucus-bound mass known as pseudofeces, which are ejected by periodic contractions of the adductor muscles.

  • pseudoforce (physics)

    Inertial force, any force invoked by an observer to maintain the validity of Isaac Newton’s second law of motion in a reference frame that is rotating or otherwise accelerating at a constant rate. For specific inertial forces, see centrifugal force; Coriolis force; d’Alembert’s p

  • pseudogene (biology)

    evolution: Molecular phylogeny of genes: Furthermore, there are two β pseudogenes (ψβ1 and ψβ2) and two α pseudogenes (ψα1 and ψα2), as well as a ζ pseudogene. These pseudogenes are very similar in nucleotide sequence to the corresponding functional genes, but they include terminating codons and other mutations that make it impossible for them to…

  • Pseudoginglymostoma brevicaudatum (fish)

    nurse shark: …the shorttail nurse shark (P. brevicaudatum). They are not related to the sand tiger shark (Carcharias taurus)—a type of sand shark inhabiting the waters above the continental shelves in most warm and temperate regions—which is sometimes referred to as the gray nurse shark.

  • pseudoglobulin (protein)

    globulin: …into the euglobulins and the pseudoglobulins. The former group is insoluble in water but soluble in saline solutions and may be precipitated in water that has been half-saturated with a salt such as ammonium sulfate. The latter group is soluble in water and has properties that resemble those of the…

  • pseudogout (pathology)

    joint disease: Congenital and hereditary abnormalities: In yet another metabolic disease, chondrocalcinosis, or pseudogout, crystals of calcium pyrophosphate are deposited in joint cartilages. There are several forms of the disease. Sometimes there are no symptoms; in other cases, symptoms are sufficiently severe to cause confusion with rheumatoid arthritis. Some cases run in families.

  • Pseudogymnoascus destructans (fungus)

    white nose syndrome: …a white fungus known as Pseudogymnoascus destructans in the skin of the nose and ears and in the membrane covering the wings. White nose syndrome is the first epizootic (epidemic) disease documented in bats and is associated with high mortality. Biologists estimated that between 5.7 million and 6.7 million bats…

  • pseudogynecomastia (pathology)

    gynecomastia: Conditions termed pseudogynecomastia are caused by excessive body fat, inflammatory disorders, granular lesions, or growth of tumours.

  • pseudohallucination (psychology)

    illusion: Illusions of psychiatric significance: Illusions called pseudohallucinations occur at times when feelings of anxiety or fear are projected on external objects, as when a child perceives threatening faces or monsters in shadows at night or sees goblins in trees. A soldier tense with apprehension may in his fear perceive inanimate objects…

  • pseudohemophilia B (pathology)

    Von Willebrand disease, inherited blood disorder characterized by a prolonged bleeding time and a deficiency of factor VIII, an important blood-clotting agent. Von Willebrand disease is caused by deficiencies in von Willebrand factor (vWF), a molecule that facilitates platelet adhesion and is a

  • pseudohermaphroditism (pathology)

    Pseudohermaphroditism, a condition in which the individual has a single chromosomal and gonadal sex but combines features of both sexes in the external genitalia, causing doubt as to the true sex. Female pseudohermaphroditism refers to an individual with ovaries but with secondary sexual

  • pseudohexagonal system (crystallography)

    Monoclinic system, one of the structural categories to which crystalline solids can be assigned. Crystals in this system are referred to three axes of unequal lengths—say, a, b, and c—of which a is perpendicular to b and c, but b and c are not perpendicular to each other. If the atoms or atom

  • pseudohypertrophic muscular dystrophy

    muscle disease: The muscular dystrophies: …that are relatively benign, the Duchenne type, which predominately affects boys, is severe. It causes difficulty in walking at about the age of four years, loss of the ability to walk at about the age of 11, and death before the age of 20, usually because of respiratory failure or…

  • pseudohypertrophy (medical disorder)

    muscle disease: Indications of muscle disease: Pseudohypertrophy, muscular enlargement through deposition of fat rather than muscle fibre, occurs in other forms of muscular dystrophy, particularly the Duchenne type.

  • pseudohypoparathyroidism (pathology)

    bone disease: Congenital bone diseases: Multiple abnormalities occur in polyostotic fibrous dysplasia, in which affected bone is replaced by fibrous connective-tissue matrix. The condition may cause multiple deformities that require surgical correction.

  • pseudoionone (chemical compound)

    isoprenoid: Monoterpenes: … to yield the important intermediate pseudoionone, from which β-ionone is produced by treatment with acid. Although β-ionone cannot be regarded as a terpene, it is of great importance as a starting material for the synthesis of vitamin A and as a component of violet-scented perfumes.

  • Pseudois (mammal)

    Blue sheep, (genus Pseudois), either of two species of sheeplike mammals, family Bovidae (order Artiodactyla), that inhabit upland slopes in a wide range throughout China, from Inner Mongolia to the Himalayas. Despite their name, blue sheep (Pseudois nayaur) are neither blue nor sheep. As

  • pseudolamellibranch ctenidium

    bivalve: Internal features: In the pseudolamellibranch ctenidium, filaments and lamellae are more securely united, and an inherent sorting mechanism still exists in some. In many, however, the filaments are vertically aggregated into folds, or plicae, that greatly increase the total surface area. In the eulamellibranch ctenidium the filaments and lamellae…

  • Pseudolarix amabilis (plant)

    Golden larch, (Pseudolarix amabilis), coniferous tree of the family Pinaceae, native to China. A golden larch resembles a tree of the true larch genus (Larix) but has small cones that fall apart when mature and club-shaped, short branchlets, or shoots, that are longer than those of Larix species.

  • pseudolaryngeal speech (physiology)

    Pseudolaryngeal speech, mechanical or esophageal speech that is taught by therapists to persons who have had the larynx, or voice box, surgically removed (laryngectomy). The operation is necessary when cancer (neoplasm) tumours are present on or near the larynx. After surgery, patients learn to

  • pseudomemory (psychology)

    False memory syndrome, the experience, usually in the context of adult psychotherapy, of seeming to remember events that never actually occurred. These pseudomemories are often quite vivid and emotionally charged, especially those representing acts of abuse or violence committed against the subject

  • pseudomonad (bacteria)

    Pseudomonad, any bacterium of the family Pseudomonadaceae, a large and varied group comprising four major genera and several hundred species. The individual cells are rod-shaped, often curved, averaging about 1 μm (micrometre; 1 μm = 10-6 metre) in diameter and several micrometres in length. The

  • Pseudomonadaceae (bacteria)

    Pseudomonad, any bacterium of the family Pseudomonadaceae, a large and varied group comprising four major genera and several hundred species. The individual cells are rod-shaped, often curved, averaging about 1 μm (micrometre; 1 μm = 10-6 metre) in diameter and several micrometres in length. The

  • Pseudomonas (bacteria genus)

    plant disease: General characteristics: Clavibacter, Erwinia, Pseudomonas, Xanthomonas, Streptomyces, and Xylella. With the exception of Streptomyces species, all are small, single, rod-shaped cells approximately 0.5 to 1.0 micrometre (0.00002 to 0.00004 inch) in width and 1.0 to 3.5 micrometres in length. Streptomycetes develop branched mycelia (narrow, threadlike growth) with

  • Pseudomonas aeruginosa (bacteria)

    ear disease: Perichondritis: …due to a particular microorganism, Pseudomonas aeruginosa. There is a greenish or brownish, musty or foul-smelling discharge from the outer-ear canal, while the affected outer ear becomes tender, dusky red, and two to three times its normal thickness. Prompt antibiotic treatment is necessary to prevent permanent deformity of the outer…

  • Pseudomonas pseudomallei (bacteria)

    melioidosis: …humans and animals caused by Pseudomonas pseudomallei. Transmission to humans occurs through contact of a skin abrasion with contaminated water or soil rather than through direct contact with a contaminated animal. Inhalation of the pathogen also is suspected as a route of infection. The term melioidosis, from the Greek, means…

  • Pseudomonas solanacearum (bacteria)

    malformation: Translocation of organs: …plants infected with the bacteria Pseudomonas solanacearum and Agrobacterium tumefaciens as well as the Fusarium wilt fungus and the cranberry false blossom virus.

  • Pseudomonas stutzeri (bacteria)

    bacteria: Heterotrophic metabolism: …as an electron acceptor, and Pseudomonas stutzeri is of major global importance for its activity in denitrification, the conversion of nitrate to nitrite and dinitrogen gas (N2). Desulfovibrio and Desulfuromonas reduce sulfate and elemental sulfur (S), respectively, yielding sulfide (S2−), and the bacterium Acetobacterium

  • Pseudomonas viridiflava (bacteria)

    basal rot: …caused by Pectobacterium carotovorum and Pseudomonas viridiflava, among others.

  • pseudomorph (mineral)

    Pseudomorph, mineral formed by chemical or structural change of another substance, though retaining its original external shape. Although pseudomorphs give the appearance of being crystalline, they are commonly granular and waxy internally and have no regular cleavage; those that are crystalline

  • Pseudomyrmex ferruginea (insect)

    Bagheera kiplingi: …stinging ants of the genus Pseudomyrmex, which live inside the swollen thorns of the trees. Pseudomyrmex ants have a well-characterized mutualistic relationship with swollen-thorn acacias; the plants depend on the aggressive nature of Pseudomyrmex to protect against animal predators, and the ants depend on the trees’ Beltian bodies and nectar…

  • Pseudonaja (reptile, genus Pseudonaja)

    Brown snake, any of several species of snakes named for their usual predominating colour. In New Guinea and Australia the name brown snake is applied to approximately 10 species of the genus Pseudonaja. These venomous snakes are slender, small-headed members of the cobra family, Elapidae. Brown

  • Pseudonaja affinis (snake)

    brown snake: nuchalis) and the dugite (P. affinis).

  • Pseudonaja nuchalis (snake)

    brown snake: …in the genus are the western brown snake (P. nuchalis) and the dugite (P. affinis).

  • Pseudonaja textilis (snake)

    brown snake: The best-known species is the eastern brown snake (P. textilis), which grows to about 2 metres (7 feet). Other species in the genus are the western brown snake (P. nuchalis) and the dugite (P. affinis).

  • Pseudopedinella (algae genus)

    algae: Annotated classification: Pedinella, and Pseudopedinella. Class Eustigmatophyceae Mostly small, pale green, and spherical; fewer than 15 species; Eustigmatos and Nannochloropsis. Class Phaeophyceae (brown algae

  • pseudoperianth (plant anatomy)

    magnoliid clade: Reproductive structures: …is actually a false, or pseudo-, perianth because it lies between the stamens and carpels rather than surrounding these reproductive structures. The pseudoperianth is thought to have evolved from sterile stamens (staminodes). It releases odours that attract beetle pollinators and is partially eaten by them. Some primitive magnoliids have a…

  • Pseudophryne corroboree (amphibian)

    Australia: Conservation: …National Recovery Plan for the southern and northern corroboree frogs. (The northern corroboree frog [Pseudophryne pengilleyi] is found mostly in the Bimberi and Brindabella Ranges of New South Wales, and the southern corroboree [P. corroboree] lives only in the Jagungal Wilderness Area of Kosciuszko National Park in New South Wales.)…

  • Pseudophryne pengilleyi (amphibian)

    Australia: Conservation: …Plan for the southern and northern corroboree frogs. (The northern corroboree frog [Pseudophryne pengilleyi] is found mostly in the Bimberi and Brindabella Ranges of New South Wales, and the southern corroboree [P. corroboree] lives only in the Jagungal Wilderness Area of Kosciuszko National Park in New South Wales.) The principal…

  • Pseudophyllidea (tapeworm order)

    flatworm: Annotated classification: Order Pseudophyllidea Scolex with 2 elongated, shallow bothria, 1 dorsal and 1 ventral; genital pore lateral or median. Vitellaria lateral or extending across proglottid and encircling other organs; parasites of teleosts and land vertebrates. Order includes the largest of all known tapeworms, Polygonoporus giganticus, which reaches…

  • Pseudopimelodidae (fish family)

    ostariophysan: Annotated classification: Family Pseudopimelodidae (bumblebee catfishes) Wide mouth, small eyes. South America. 5 genera, 26 species. Family Aspredinidae (banjo catfishes) Adipose lacking; broad, flat head; large tubercles on naked body. Aquarium fishes. Size to 30 cm (12 inches). A few enter brackish waters and salt waters. South America. 12…

  • pseudoplasmodium (mycology)

    Plasmodium, in fungi (kingdom Fungi), a mobile multinucleate mass of cytoplasm without a firm cell wall. A plasmodium is characteristic of the vegetative phase of true slime molds (Myxomycetes) and such allied genera as Plasmodiophora and Spongospora. The plasmodium of a slime mold is formed from

  • Pseudopleuronectes americanus (fish)

    flounder: …pounds) in weight; and the winter flounder (Pseudopleuronectes americanus), an American Atlantic food fish, growing to about 60 cm (23 inches) in length. Flounders in that family typically have the eyes and colouring on the right side.

  • pseudopod (anatomy)

    dipteran: Larvae: …larvae have “false legs” (prolegs or pseudopods) similar to those that support the fleshy abdomen of a caterpillar. Flies, much more versatile in this respect than caterpillars, can have prolegs around any body segment. Prolegs help the larvae crawl through narrow spaces or push through soil.

  • pseudopod (cytoplasm)

    Pseudopodium, temporary or semipermanent extension of the cytoplasm, used in locomotion and feeding by all sarcodine protozoans (i.e., those with pseudopodia; see sarcodine) and some flagellate protozoans. Pseudopodia are formed by some cells of higher animals (e.g., white blood corpuscles) and by

  • pseudopodia (cytoplasm)

    Pseudopodium, temporary or semipermanent extension of the cytoplasm, used in locomotion and feeding by all sarcodine protozoans (i.e., those with pseudopodia; see sarcodine) and some flagellate protozoans. Pseudopodia are formed by some cells of higher animals (e.g., white blood corpuscles) and by

  • pseudopodial locomotion (biology)

    locomotion: Pseudopodial locomotion: Although ciliar and flagellar locomotion are clearly forms of appendicular locomotion, pseudopodial locomotion () can be classed as either axial or appendicular, depending upon the definition of the pseudopodium. Outwardly, pseudopodial locomotion appears to be the extension of a part of the body…

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