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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.
A subclass of the annelid worms commonly known as leeches. These organisms are parasitic or predatory and have terminal suckers for attachment and locomotion. Most inhabit inland waters, but some are marine and a few live on land in damp places. The majority feed by sucking the blood of other animals, including humans.
Industry:Science
A subclass of the class Bryopsida, the true mosses. It consists of a single family with four genera. The peristome shows some similarities to the double-peristome members of the subclass Bryidae, but the numerous series of teeth external to the endostomial cone are distinctive.
Industry:Science
A subclass of the class Bryopsida. Most genera of true mosses (Bryopsida) belong in the 16 orders of the Bryidae. The most characteristic feature is the peristome consisting of one or two series of teeth, derived from parts of cells rather than whole cells, as in the Tetraphididae, Dawsoniidae, and Polytrichidae. (The Buxbaumiidae have some resemblance in peristome structure to Bryidae.)
The stems may be erect and merely forked, or prostrate and freely branched, with sporophytes produced terminally or laterally, respectively. The leaves are inserted in many rows, though sometimes flattened together and appearing two-ranked, but only rarely actually in two rows. The costa may be single or double, sometimes very short, and rarely lacking. The cells are short or elongate, thin- or thick-walled, and often papillose-roughened. The basal and especially the basal angular cells are often differentiated. The setae are generally present and elongate. The capsules dehisce by means of an operculum except in a few genera that show extreme reduction. The number of peristome teeth and segments of the inner peristome are usually 16. The spores are produced by two layers of spore mother cells; they are generally small. The calyptra may be cucullate or mitrate.
Industry:Science
A subclass of the class Insecta comprising the winged insects and their secondarily wingless descendants. This subclass, including the great majority of insects, is usually divided into two infraclasses: Paleoptera, or ancient-winged insects (mayflies, dragonflies, and several extinct orders, most of which could not fold the wings over the body), and Neoptera, or folding-winged insects (the rest of the winged insects and some secondarily wingless lineages), which ancestrally folded the wings over the body by a particular articulatory mechanism.
Industry:Science
A subclass of the class Liliopsida (monocotyledons) of the division Magnoliophyta (Angiospermae), the flowering plants, consisting of 2 orders (Liliales and Orchidales), 19 families, and about 25,000 species. The Liliidae are syncarpous monocotyledons with both the sepals and the petals usually petaloid. The seeds are either nonendospermous or have an endosperm with various sorts of reserve foods such as cellulose, fats or protein, and only seldom starch. The stomates are without subsidiary cells or, in a few small families, have two subsidiary cells. The pollen is binucleate. The vast majority of the species have the vessels chiefly or wholly confined to the roots. The flowers generally have well-developed nectaries, and pollination is usually by insects or other animals.
Industry:Science
A subclass of the class Liliopsida (monocotyledons) of the division Magnoliophyta (Angiospermae), the flowering plants, consisting of 7 orders, 16 families, and nearly 15,000 species. The orders include Commelinales, Eriocaulales, Restionales, Juncales, Cyperales, Hydatellales, and Typhales. For further information see separate articles on each order.
Industry:Science
A subclass of the class Liliopsida (monocotyledons) of the division Magnoliophyta (Angiospermae), the flowering plants, consisting of four orders (Arecales, Cyclanthales, Pandanales, and Arales), five families, and nearly 6000 species. Except for the highly reduced family Lemnaceae (Arales), they have an inflorescence of usually numerous, small flowers, generally subtended by a prominent spathe and often aggregated into a spadix. Except in the Araceae (Arales), the endosperm seldom contains much starch.
Industry:Science
A subclass of the class Magnoliopsida (dicotyledons) in the division Magnoliophyta (Angiospermae), the flowering plants. The subclass consists of 8 orders, 39 families, and more than 12,000 species. The Magnoliidae are the most primitive subclass of flowering plants, being essentially coextensive with what has often been called the Ranalian complex. In general, they have a well-developed perianth, which may or may not be numerous, centripetal stamens, and they are apocarpous. Their ovules are bitegmic and crassinucellate, and their seeds usually have a small embryo and copious endosperm. All of these characters are subject to exception, however, and there is no one character or easy set of characters by which the group can be formally defined.
Various other putatively primitive characters, such as vesselless xylem, laminar stamens, laminar placentation, and the presence of more than two cotyledons, are largely or wholly restricted to this subclass, but are not standard features.
Industry:Science
A subclass of the class Telosporea. These protozoa are typically intracellular parasites of epithelial tissues in both vertebrates and invertebrates. The group is divided on the basis of life cycles into two orders, the Protococcida (in which there is only sexual reproduction) and the Eucoccida (in which there is both sexual and asexual reproduction). There are only a few species in Protococcida, and all are parasites in marine invertebrates. There are hundreds of species in Eucoccida; these are parasites in both invertebrates and vertebrates. The Eucoccida contains three suborders: Adeleina, which occur mostly in invertebrates and in which there is usually one host for the sexual stages and a different host for the asexual stages (an example is <i>Hepatozoon muris</i>, found in rats and transmitted by mites); Haemosporina, which occur mainly in vertebrates and which have their sexual stages in invertebrates (an example is <i>Plasmodium falciparum</i> which causes malaria in humans and is transmitted by mosquitoes); and Eimeriina, which occur mostly in vertebrates and in which the sexual and asexual stages occur in the same host (an example is <i>Eimeria</i>, species of which cause coccidiosis in many domestic animals and wildlife, and which are transmitted by filth). The malaria parasites and coccidia are of direct importance to humans, and also cause important losses in chickens, cattle, sheep, and other domesticated animals.
Industry:Science
A subclass of the molluscan class Gastropoda, containing about 23,500 species of snails that are grouped into three orders (or superorders): Systellommatophora, Basommatophora, and Stylommatophora. Pulmonates include most of the common snails found on land or in fresh waters, although a few prosobranchs have invaded both habitats. Certain pulmonates, the Onchidiidae, Amphibolidae, Otinidae, Siphonariidae, Trimusculidae, and some members of the Ellobiidae are intertidal to subtidal on rocky shores of tropical and temperate regions.
Industry:Science
