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McGraw Hill Financial, Inc. is an American publicly traded corporation headquartered in Rockefeller Center in New York City. Its primary areas of business are financial, publishing, and business services.
An order of the class Toxoplasmea. Four genera, <i>Toxoplasma, Besnoitia, Sarcocystis</i>, and <i>Encephalitozoon</i>, make up the order. The organisms are parasites of vertebrates. <i>Toxoplasma</i> is often found encysted in nerve tissue, <i>Besnoitia</i> in connective tissue, and <i>Sarcocystis</i> in muscle. Very little is known about <i>Encephalitozoon</i>, but the parasite has been found in the brain of rabbits.
Industry:Science
An order of the class Zoomastigophorea in the phylum Protozoa, also known as Protomastigida, containing a heterogeneous group of colorless flagellates possessing one or two flagella in some stage of their life cycle. These small organisms (5–89 micrometers in length) typically have pliable bodies. Some species are holozoic and ingest solid particles, while others are saprozoic and obtain their nutrition by absorption. Their life cycles are usually simple but some species have two or more recognizably distinct stages. The species may be either free-living or parasites of vertebrates, invertebrates, and plants. Reproduction is by longitudinal fission, although multiple fission occurs in some species. Several are important disease-causing parasites of humans and domestic and wild animals.
Industry:Science
An order of the class Zoomastigophorea, phylum Protozoa. These are small, colorless flagellates, some of which are free-living and some parasitic. The body of this protozoan is bilaterally symmetrical, composed of two mirror halves, each with a nucleus and a full set of organelles. There are four flagella to a side, not all of the same length. In division of the cell the two nuclei each form a spindle, so that each daughter cell receives two nuclear complexes.
Industry:Science
An order of the cnidarian class Scyphozoa, usually found in circumpolar regions. <i>Haliclystus auricula</i> is typical. The egg develops into a planula which can only creep since it lacks cilia. The planula changes into a polyp that metamorphoses directly into a combined polyp and medusa form. The medusa is composed of a cuplike bell called a calyx (medusan part) and a stem (polyp part) which terminates in a pedal disk. The calyx is eight-sided and has eight groups of short, capped tentacles and eight sensory bodies, called anchors (rhopalioids), on its margin. The mouth, situated at the center of the calyx, has four thin lips and leads to the stomach in which gastral filaments are arranged in a row on either side of each interradius. Though sessile, the medusa can move in a leechlike fashion by alternate attachment and release of the pedal disk, using the substratum as an anchor.
Industry:Science
An order of the cnidarian subclass Alcyonaria (Octocorallia) which lacks coenenchyme (the gelatinous layer, or mesoglea, surrounding and uniting the polyp). They form either simple (<i>Cornularia</i>) or rather complex colonies (<i>Tubipora</i>). The polyp has a cylindrical body with a retractile oral portion which can withdraw into a solid anthostele (the basal portion of the polyp) or calyx protected by many calcareous spicules. <i>Cornularia</i>, with a horny investment, lacks spicules. The base of the mature polyp is attached to a creeping stolon which is a ribbonlike network or thin flat mat from which daughter polyps arise. Daughter polyps never bud from the wall of the primary polyp. Each polyp is connected by solenial tubes of the stolons, or by transverse platforms as in <i>Tubipora</i>.
Industry:Science
An order of the cnidarian subclass Alcyonaria (Octocorallia). The Coenothecalia have no spicules but form colonies with a massive skeleton composed of fibrocrystalline argonite fused into lamellae. The skeleton is perforated by both numerous wide cylindrical cavities occupied by the polyps, and narrow ones containing the solenial systems. In the calyx of the polyp, septalike structures of stony coral, or pseudosepta, are formed. The order includes a few genera, of which <i>Heliopora</i>, or the blue coral, is often found on coral reefs.
Industry:Science
An order of the cnidarian subclass Alcyonaria (Octocorallia). Telestacea are typified by <i>Telesto</i>, which forms an erect branching colony by lateral budding from the body wall of an elongated primary or axial polyp. The stolon is bandlike or membranous. Sclerites are scattered singly, partly fused, or entirely fused to form a rigid tube.
Industry:Science
An order of the cnidarian subclass Alcyonaria. The Gorgonacea are the horny corals which often form fanlike or featherlike colonies with branches spread radially or oppositely in one plane. They attach to objects by somewhat enlarged bases of tufts of stolons. They are more widely distributed than the Alcyonacea and extend from the littoral zone to some great depth.
Industry:Science
An order of the cnidarian subclass Hexacorallia. Sometimes known popularly as “mat anemones” and technically also as Zoanthiniaria (the name Zoantharia is an alternative for subclass Hexacorallia), this order contains relatively few species.
Industry:Science
An order of the cnidarian subclass Zoantharia (Hexacorallia) known as the sea anemones, the most widely distributed of the anthozoans. They have even been discovered in frigid waters. Usually they are solitary animals which live under the low-tide mark attached to some solid object by a basal expansion or pedal disk. They feed on prey such as copepods, mollusks, annelids, crustaceans, and fishes. The burrowing species, like <i>Edwardsia</i>, <i>Halcampella</i>, and <i>Harenactis</i>, lack a pedal disk and bury their elongated bodies in the soft sediment of oceans. The actinians move rather actively. <i>Gonactinia</i> and <i>Boloceroides</i> can swim by using their tentacles.
Industry:Science
