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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 small, slender insects, commonly called thrips, having exopterygote development, sucking mouthparts, and highly modified wings. The order is a relatively small one, but individuals are often very numerous in favorable environments.
Industry:Science
An order of somewhat intermediate position among actinopterygian fishes. It shares with the perciforms fin spines and ctenoid scales, an upper jaw bordered by the premaxillae, a ductless swim bladder, and absence of a mesocoracoid. An orbitosphenoid bone is present, as is typical of many lower teleosts. The pelvic fins are thoracic or subabdominal in position, and each has a spine and 3 to 13 (usually more than 5) soft rays; the pelvic girdle is most often attached to the cleithra; and there are 18 or 19 principal caudal rays.
Industry:Science
An order of sponges of the class Demospongiae with monactinal megascleres that usually have a terminal knob at one end. Microscleres in the form of streptasters, asters, sigmas, or small spined diactinals may occur. Megascleres tend to be arranged in tracts radiating from the center of the sponge; spongin is usually sparse in occurrence.
Industry:Science
An order of sponges of the class Demospongiae, subclass Tetractinomorpha, with a globular shape and a skeleton of oxeas and triaenes as megascleres, and microspined, contorted, sigmalike microscleres.
Industry:Science
An order of sponges of the subclass Hexasterophora in the class Hexactinellida. The parenchymal mega-scleres in this order are united to form a rigid framework and consist wholly of simple hexactins which are arranged in parallel linear series. The members of each series are united one to another by a secondary envelope of silica. Examples include <i>Hexactinella</i>, <i>Aphrocallistes</i>, <i>Eurete</i>, and <i>Farrea</i>.
Industry:Science
An order of Squalomorpha that are known as the six-gill sharks. These sharks are distinguished by a combination of the following characters: six or seven gill slits, all anterior to the pectoral fins; a single dorsal fin without a spine; anal fin present (the only order of squalomorphs with an anal fin); the dorsal, anal, and pelvic fins placed far posteriorly; eyes lacking a nictitating fold or membrane (at the inner angle of the eye or below the eyelid that is capable of extending over the eyeball); spiracles present, but small and well behind the eyes; and ovoviviparous development. They comprise two extant families (chlamydoselachidae and Hexanchidae), four genera, and five species.
Industry:Science
An order of tardigrades, lacking a cirrus lateralis, a sensory cephalic appendage, and a clava, or club-shaped appendage. Pharyngeal pockets are strengthened by separated rods or macroplacoids or are without thickenings. Claws are of different size, arranged in two pairs in which a larger and smaller claw are united. In <i>Milnesium</i> the claws are separated. <i>Haplomacrobiotus</i> has two simple claws. Eight longitudinal muscles are associated with the midgut. At the beginning of the hindgut, there are three excretory glands, called the vasa malpighii, which are specifically stretched or trilobed. Each gland is composed of three cells. The gonoducts open into the rectum, resulting in a single opening known as the anogenital pore or cloaca.
Industry:Science
An order of teleost fishes characterized by a compressed head and body, usually large lateral eyes, large terminal mouth and adipose fin, usually eight pelvic rays, and deep-sea pelagic (living in the open oceans or seas) and benthopelagic (bottom-dwelling) habits. There are two families: Neoscopelidae (blackchins) and Myctophidae (lanternfishes).
Industry:Science
An order of teleost fishes composed of about 257 species, most of which have a small mouth at the end of a long tubular snout and body armor of dermal plates or bony rings. They are further identified by the absence of supramaxillary, orbitosphenoid and basisphenoid bones; and a pelvic girdle that is not connected to the cleithra. Gasterosteiforms are carnivorous predators, feeding chiefly on crustaceans, which they siphon from the water with their tubelike mouthparts. Large species such as trumpetfishes and cornetfishes are primarily piscivorous. Sticklebacks, pipefishes, and seahorses are popular aquarium fishes.
Industry:Science
An order of teleost fishes comprising eight families, 88 genera, and about 810 species that inhabit fresh and brackish waters of tropical and temperate North and Middle America, Eurasia, and Indo-Malaysia. Several features unify the order: a symmetrical caudal skeleton of one epural supporting an unlobed (round) caudal fin; low-set pectoral fins with a large, scalelike postcleithrum; sensory pores chiefly on the head; and the upper jaw bordered by protractile premaxillae. Sexual dimorphism is common, with the males brightly colored, and, in the livebearers, an anal fin that is modified as a gonopodium (intromittent organ) for internal fertilization. The top of the head is usually flat and the mouth is usually terminal to superior, features that adapt the fishes to feed on or near the surface of the water.
Industry:Science
