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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 phylum Ctenophora (comb jellies) comprising the families Bathocyroidae, Bolinopsidae, Eurhamphaeidae, Kiyohimeidae, Leucotheidae, and Ocyropsidae. Lobate ctenophores are characterized by large winglike lobes on the oral end of the body that are used for capturing food. All species are predators on zooplankton. Lobates are among the largest ctenophores; some epipelagic species attain an oral-aboral height of 8 in. (20 cm), and some deep-sea species have lobes nearly 39 in. (1 m) across. Most species are transparent, but some have conspicuous brown, blue, or purple spots on the lobes. Deep-sea forms often have red pigment surrounding the stomodeum. Lobates are bioluminescent, like other ctenophores. Bright blue-green light is produced in the meridional canals, and some species also release a cloud of luminous material into the water when disturbed, probably as part of an escape response.
Industry:Science
An order of the phylum Ctenophora (comb jellies) comprising two genera, <i>Beroë</i> and <i>Neis</i>. The single species of <i>Neis (N. cordigera)</i> is known only from Australia, but many species of <i>Beroë</i> have been described from polar to tropical waters all over the world. Beroids are predators on other ctenophores and occur in all parts of the water column where ctenophores are found.
Industry:Science
An order of the phylum Protozoa, subphylum Sarcomastigophora, superclass Mastigophora, class Phytamastigophorea. These organisms are marine flagellates which have an internal, siliceous, tubular skeleton; numerous small, discoid, yellow chromatophores; and a single flagellum. At times the organisms also put forth, from the ends of their skeletal tubes, long, rather threadlike pseudopodia. The skeleton forms a basket within which the moiety of protoplasm lies, but skeletal elements always have at least a thin covering. Nuclei are not conspicuous. Reserve material consists of leucosin.
Industry:Science
An order of the Podocopa (Ostracoda) containing a single family, Cytherellidae, and two extinct superorders. Platycopids are small marine or brackish-water ostracods with an asymmetrical shell that is oblong, nearly rectangular, and laterally compressed; their six pairs of appendages are adapted for burrowing and filter feeding. Both fossil and living species have the inner lamella of each valve calcified only in the distal rim, if at all; if a narrow duplicature is developed, it is continuous with the outer lamella and does not form a vestibule (troughlike cavity) between the lamellae. Recent platycopids are distinct from all other ostracods: The larger valve is rabbeted to overlap the smaller around the free edge; the carapace lacks vertical lobation; none of the postoral appendages serve as legs; and the posterior end of the body is more clearly delimited and tapering than in other ostracods.
Industry:Science
An order of the Protozoa in the class Zoomastigophorea comprising the most complex flagellates, both structurally and in modes of division. All inhabit the alimentary canal of termites, cockroaches, and woodroaches. These organisms are multiflagellate, often with complicated blepharoplast-parabasal-axostylar structures. The nucleus is single and the organisms are plastic and slow-moving, generally ovoid to elongate. Flagella occur in spiral rows, in tufts, or over the entire body. These flagellates vary from 15 to 350 micrometers in size. They may be holozoic or saprozoic. Ingestion is usually pseudopodial, in the posterior region. A high degree of adaptiveness exists, and species peculiar to one host species are not viable in another. Sexual processes and multiple fission are known, but trinary fission is most common. <i>Holomastigotoides</i> has spirochetes attached to its trophic body zone.
Industry:Science
An order of the protozoan class Myxosporidea (subphylum Cnidospora). It is characterized by the production of spores with one or more valves and polar capsules, and by possession of a single sporoplasm with or without an iodinophilous vacuole. Myxosporidians are mainly parasites of fishes. They infect all parts of the body, including the heart and brain, and often induce considerable pathological changes in the host tissue.
Industry:Science
An order of the protozoan class Myxosporidea (subphylum Cnidospora). It is characterized by the production of trivalved spores with three polar capsules and one to many sporoplasms. The spore membrane may be extended into anchor-shaped processes, which may have bifurcate tips. These protozoan parasites are found in the body cavity or in the intestinal lining of fresh-water annelids and in marine worms of the phylum Sipunculoidea.
Industry:Science
An order of the protozoan class Phytamastigophorea. This order of protozoa is also known as Euglenoidina, and botanists classify the group in the class Euglenophyceae. The euglenids include the largest green noncolonial flagellates, <i>Euglena ehrenbergii</i>, which are 400 micrometers long. Many of the colorless members are also large. They have one or two equal or subequal flagella. There are relatively few genera of Euglenida, even if doubtful ones such as <i>Clorachne</i> and <i>Ottonia</i> are included. The fresh-water genera <i>Euglena</i>, <i>Lepocinclis</i>, <i>Phacus</i>, and <i>Trachelomonas</i> have many species, as does the colorless genus <i>Petalomonas</i>. Others have few species, including the marine genus <i>Eutreptia</i>. <i>Calkinsia</i> is yellow, some euglenas are red at times, and all others are green or colorless, although <i>Trachelomonas</i> tests are frequently colored by iron.
Industry:Science
An order of the protozoan subclass Gregarinia, class Telosporea, subphylum Sporozoa. All gregarines are parasites of the digestive tract and body cavity of invertebrates or lower chordates; their large, mature trophozoites (vegetative stages) live outside the host's cells. The Archigregarinida are primitive gregarines, and live in marine worms (annelids and lower chordates—enteropneustids, sipunculids, and ascidians). Their life cycle includes sexual and asexual phases and involves three periods of schizogony (multiple fission).
Industry:Science
An order of the protozoan subclass Gregarinia, class Telosporea, subphylum Sporozoa. All gregarines are parasites of the digestive tract and body cavity of invertebrates or lower chordates; their mature trophozoites (vegetative stages) live outside the host's cells and are large. The Neogregarinida are thought to be relatively advanced gregarines which live in insects. The most primitive gregarines, the Archigregarinida, differ from the typical gregarines, the Eugregarinida, in having asexual multiple fission (schizogony) before gamonts (cells which will produce gametes) are formed. The Neogregarinida are thought to have acquired this trait secondarily and to have developed from the Eugregarinida.
Industry:Science
