. An introduction to the osteology of the mammalia . ed expansions of the skin. Among the INSECTIVORA, the scaphoid and lunar coalescein Galeopithecus, Tupaia, Ctntetes, Sohnodon, Erinaceus, andGymnura^ but in most of the other forms these bones aredistinct. A distinct os centrale is found in all exceptGaleopithecus, Potamogale, Chrysochloris, and Sorex. There are nearly always five digits, but Rhynchocyon,Oryzoryctes tetradactylus and Chrysochloris have but four,the pollex being absent. The whole hand is generallyof moderate size, with pointed, conical, slightly curved,ungual phalanges. In co
. An introduction to the osteology of the mammalia . ed expansions of the skin. Among the INSECTIVORA, the scaphoid and lunar coalescein Galeopithecus, Tupaia, Ctntetes, Sohnodon, Erinaceus, andGymnura^ but in most of the other forms these bones aredistinct. A distinct os centrale is found in all exceptGaleopithecus, Potamogale, Chrysochloris, and Sorex. There are nearly always five digits, but Rhynchocyon,Oryzoryctes tetradactylus and Chrysochloris have but four,the pollex being absent. The whole hand is generallyof moderate size, with pointed, conical, slightly curved,ungual phalanges. In common with every segment of the anterior extremity,the manus of the Mole (Talpd] and its immediate allies isextremely modified to suit its fossorial habits (see Fig 95). u 290 THE .IfANUS. [CM A!. It is extremely broad and strong, its breadth being increasedby the great development of the radial sesamoid (rs), which,being sickle shaped, has received the special name of osfaldforme. The ungual phalanges are very large, and cleftat their extremities V. u FIG. 95. —Bones of fore-arm and manus of Mole {Tajpa euro/cca) X 2. R radius ;U ulna ; s scaphoid ; / lunar ; c cuneiform ; f> pisiform ; u unciform ; m magnum :rd trapezoid ; tin trapezium ; ^central; rs radial sesamoid (falcifonn) ; i—v thedigits. In the CHIROPTERA, the hand is especially modified in atotally different manner, constituting the organ of flight. In the carpus the scaphoid and lunar are united, and insome genera (as Ptcropus) the cuneiform is joined with them,so that the proximal row contains but a single bone. Thereis no centrale. The pisiform is very small. XVI.] CHIROPTERA. 291 The pollex is short, divaricated from the other digits, notenveloped, as they are, in a cutaneous expansion, and armedwith a curved claw. The other digits are extremely long andslender. In the Frugivorous Bats (Fteropidaz) the second digit has ashort ungual phalanx and claw, but in each of the other si .m
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectbones, bookyear1885
