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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 small order of birds that contains only the family Trogonidae. Thirty-seven species are found throughout the tropics; two species reach the southern border of the United States. The trogons and quetzals are jay-sized birds with large heads, and tails that vary from medium length and squared to very elongated and tapered. The dorsal plumage of trogons and quetzals is predominantly metallic green, with blue, violet, red, black, or gray in a few. The ventral feathers are bright red, yellow, or orange. Despite their vivid coloration, the birds are inconspicuous when sitting quietly in the forest. Quetzals possess long tapered tails of upper covert feathers, not tail feathers. Trogon plumage is soft with lax feathers. Sexes are dissimilar in appearance, with the males being more brightly colored. The head is large and rounded, and the bill is small and weak. Legs are short and feet are weak, with the toes arranged in a heterodactyl fashion, with the first and second toes reverted, opposing the third and fourth toes. Flight is rapid, undulating, and brief; trogons rarely walk. The diet consists of fruit and small invertebrates, as well as insects caught in flight as the bird darts out from a perch.
Industry:Science
A small order of diverse aquatic, mainly marine, fish-eating birds that includes the pelicans (see <b>illustration</b>), boobies, and cormorants. The members of the order, found worldwide, are very different, and some researchers believe that this “order” is an artificial group; however, all members are characterized by several unique features (for example, a bare throat pouch).
Industry:Science
A small order of flowering plants (3600 species) in the eumagnoliid group, which is composed of three anomalously woody vines (shrubs) or herbaceous families—the pipeworts (Aristolochiaceae), the black pepper family (Piperaceae), and the lizard's tail family (Saururaceae). The last two families have reduced flowers in dense spikelike flower stems, and the first has medium-sized to enormous flowers that often trap insects for a period before releasing them, covered with pollen.
Industry:Science
A small order of flowering plants, division Magnoliophyta (Angiospermae), in the subclass Dilleniidae of the class Magnoliopsida (dicotyledons). It consists of two small families and fewer than 20 species, of no economic significance. The plants are trees, shrubs, or subshrubs with simple, entire leaves and small, unisexual flowers. The perianth consists of small, separate or fused sepals with no petals. The stamens are four to numerous; the pistil has (1)2–many carpels, fused to form a plurilocular, superior ovary. The fruit is a dry, dehiscent nutlet or a drupe. The taxonomic disposition of the Batales has long been disputed, and it is often included in the Caryophyllidae. However, the presence of mustard oils as well as certain morphological features suggest that the order is best included near the Capparales in the Dilleniidae.
Industry:Science
A small order of flowering plants, division Magnoliophyta (Angiospermae), which gives its name to the subclass Alismatidae of the class Liliopsida (monocotyledons). It consists of three families (Alismataceae, Butomaceae, and Limnocharitaceae) and less than a hundred species. They are aquatic and semiaquatic herbs with a well-developed, biseriate perianth that is usually differentiated into three sepals and three petals, and with a gynoecium of several or many, more or less separate carpels. Each flower is usually subtended by a bract. <i>Butomus umbellatus</i> (flowering rush) and species of <i>Sagittaria</i> (arrowhead, family Alismataceae) of this order are sometimes cultivated as ornamentals.
Industry:Science
A small order of flowering plants, division Magnoliophyta (Angiospermae), which gives its name to the subclass Hamamelidae in the class Magnoliopsida (dicotyledons). The family Hamamelidaceae contains about 100 species and the Platanaceae about 6 species; the other 3 families have only 2 species each. Within its subclass, the order is more advanced than the Trochodendrales in having vessels in the wood, but less advanced than the other orders in that the gynoecium consists either of separate carpels or of united carpels that open at maturity to release the seeds. Witch hazel (<i>Hamamelis</i>; see <b>illus.</b>), sweet gum (<i>Liquidambar</i>, family Hamamelidaceae), and the plane tree or sycamore (<i>Platanus</i>) are familiar members of the Hamamelidales.
Industry:Science
A small order of heterosporous, leptosporangiate ferns (division Polypodiophyta) which float on the surface of the water. The delicate, branching stem becomes as much as 1 in. (2.5 cm) or so long and is provided with small, simple to bifid or more or less dissected leaves. The sporangia are enclosed in specialized appendages of the leaves, called sporocarps. A sporocarp contains numerous microsporangia or a single megasporangium, but not both types. The order contains only a single family, with two widely distributed genera, <i>Salvinia</i> and <i>Azolla</i>, with only about 20 species in all. <i>Azolla</i> is of some interest because of its symbiotic relationship with <i>Anabaena azollae</i>, a nitrogen-fixing blue-green alga which inhabits specialized chambers in the leaves.
Industry:Science
A small order of heterosporous, leptosporangiate ferns (division Polypodiophyta) which grow in water or wet places and are rooted to the substrate. The leaves arise on long stalks from the rhizome and typically have floating blades with four leaflets, suggesting a four-leaved clover. The sporangia are enclosed in modified folded leaves or leaf segments called sporocarps. Megasporangia and microsporangia are borne in the same sporocarp. The order contains a single family and only 3 genera, about 50 species in all, most of them belonging to the widespread genus <i>Marsilea</i> (water clover).
Industry:Science
A small order of insects called the scorpion flies. Characteristic of the adult insect is the peculiar prolongation of the head into a beak, which bears chewing mouthparts. They are small to medium in size. The insects either have two pairs of large, net-veined wings of equal size, often with dark areas, or have short and aborted wings. The legs are long and slender. In some species, the male abdomen has a terminal enlargement which is held recurved over the back so that he resembles a scorpion, thus the common name (see <b>illus.</b>). The larvae are eruciform (resembling caterpillars), and the pupae exarate; that is, the appendages are free from the body and artificially movable. The Mecoptera are found in moist habitats within densely wooded areas. The adults are omnivorous but feed chiefly on small insects.
Industry:Science
A small order of specialized holostean fishes which are first recorded from Middle Jurassic deposits of Europe. Later records indicate that they were a very successful group in terms of geographic range, and probably had a worldwide distribution in the warm seas of the Cretaceous Period. The order contains one family, Aspidorhynchidae, and two genera, <i>Aspidorhynchus</i> and <i>Belonostomus</i>. These fishes, some of which reached a length of over 3 ft (0.9 m), are characterized by a ganoid scale covering with much deepened scales along the flank, by an elongate fusiform body and head with long slender snout, and by an externally symmetrical tail. All the fins are small, and fringing fulcra are reduced or absent. The dorsal and anal fins are positioned opposite one another far back on the body, and the pelvic fins are inserted closer to the anal than to the pectorals (see <b>illus</b>.). The vertebral column shows a fair amount of ossification with thin ringlike or half centra.
Industry:Science
