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An order of the Reptilia, subclass Anapsida, including the turtles, terrapins, and tortoises. This order is also known as the Testudines. The group first appeared in the Triassic, and its representatives are among the commonest fossils from that time on. Members of the order are most frequently found in fresh-water streams, lakes, and ponds or in marshy areas. However, a number of strictly terrestrial species are known, and several are marine. Turtles occur on all the major continents and continental islands in tropic and temperature regions. The marine forms are basically tropic in distribution, but some individuals stray into temperate waters.
Industry:Science
An order of the subclass Amphidiscophora in the class Hexactinellida. These sponges are distinguished from the order Amphidiscosa in that the birotulates are hemidiscs with asymmetrical ends. <i>Hemidiscella</i> from the Cretaceous is an example.
Industry:Science
An order of the subclass Amphidiscophora in the class Hexactinellida. These sponges are distinguished from the order Hemidiscosa in that the birotulates are amphidiscs. Examples of this order are <i>Pheronema, Monorhaphis</i>, and <i>Hyalonema</i>.
Industry:Science
An order of the subclass Bryidae. With 11 families and perhaps 44 genera, it is defined in terms of terminal inflorescences, with rare exceptions, and perfect, double peristomes which are papillose on the outer surface. The capsules are generally inclined and more or less pear-shaped. Erect capsules are associated with reduced peristomes.
Industry:Science
An order of the subclass Calcaronea in the class Calcarea. This order comprises a rather diverse group of calcareous sponges, and includes the families Sycettidae, Heteropiidae, Grantiidae, Amphoriscidae, and Lelapiidae. Choanocytes with apical nuclei are limited to flagellated chambers and never occur lining the general spongocoel. The family Sycettidae resembles the contrasting order Leucosoleniida in lacking the true dermal membrane or cortex possessed by the other five families. The most massive skeleton (of bundles of modified triradiate spicules) is found in the family Lelapiidae, which superficially resembles the unrelated pharetronid sponges (abundant in the Permian and Triassic periods). The canal system is never asconoid (as in Leucosoleniida), but can be either syconoid or leuconoid. Leuconoid species seem to be derived from syconoid forms. Genera include <i>Grantia</i>, <i>Sycon</i>, <i>Sycetta</i>, <i>Heteropia</i>, <i>Amphoriscus</i>, and <i>Leucilla</i>.
Industry:Science
An order of the subclass Hexasterophora in the class Hexactinellida. This is a group of Paleozoic hexactinellids with a branching form. Each branch is provided with dermal, parenchymal, and gastral spicule reticulations. <i>Titusvillia</i> from the Mississippian Period is an example.
Industry:Science
An order of the subclass Podocopa, class Ostracoda, that consists of the extant suborder Podocopina and the extinct Metacopina. There is agreement on the assignment of the Cypridoidea, Bairdioidea, Cytheroidea, and Darwinuloidea to the Podocopida; however, some researchers also include the Sigillioidea, and others consider the Terrestrichtheroidea a podocopid taxon of equivalent rank. In all podocopids the two valves fit firmly, hermetically sealing the animal inside when closed. Although variously sculptured, none of the podocopids have strong vertical lobation like that found in the Paleocopa.
Industry:Science
An order of the tardigrades, the majority of whose genera have widely varied structure. Cephalic appendages having a sensorial function are present, as well as cirrus lateralis and clava. Pharyngeal pockets are strengthened by uninterrupted ridges, except in <i>Pseudechiniscus islandicus</i>, which has interrupted ones. Toes or claws are uniform in structure and completely separated from one another. A preanal gonopore is present; excretory glands are absent. This order of tardigrades is divided into two suborders, Arthrotardigrada and Echiniscoidea.
Industry:Science
An order of the true mosses (Bryidae), consisting of one family and five or six genera. The plants grow on rocks, and may be exceedingly small and gregarious to moderate in size and tufted. Though the gametophytes resemble the Dicranales, the double structure of the peristome is distinctive.
Industry:Science
An order of the true mosses (subclass Bryidae) consisting of five families and 23 genera. The plants grow in mats or tufts in relatively exposed places, on trunks of trees and on rock. They are rather freely branched and prostrate, or may be sparsely forked and erect-ascending; the habit is more or less pleurocarpous, but sporophytes may be produced at the ends of leading shoots or branches. The leaves are generally oblong and broadly pointed, with a strong midrib. The upper cells are short and often papillose, while the basal cells are longer and often pellucid. The capsules are generally immersed and often ribbed, and the peristome, if present, has a poor development of endostome. The calyptrae are nearly always mitrate and often hairy. The Grimmiales, likewise somewhat pleurocarpous, differ in having single peristomes and a lesser development of neck tissue below the spore-bearing portion of the capsule.
Industry:Science
