. An introduction to zoology : for the use of high schools . less rudimentarycharacter of the pelvis indicate less departure from the typicalmammalian form than is to be seen in the Cetacea. One ofthe forms, the northern sea-cow, (Jihi/tina), exterminated littlemore than a century ago, was previously abundant on theshores of Siberia and Kamschatka. It was toothless, themouth being provided with four horny-toothed pads, whichserved in place of the grinders of the living forms. aremore numeious in the manatee, than in the dugongof the Indian HIGH SCHOOL ZOOLOGY. IG-i Ocean (IfaUcore, Fig.
. An introduction to zoology : for the use of high schools . less rudimentarycharacter of the pelvis indicate less departure from the typicalmammalian form than is to be seen in the Cetacea. One ofthe forms, the northern sea-cow, (Jihi/tina), exterminated littlemore than a century ago, was previously abundant on theshores of Siberia and Kamschatka. It was toothless, themouth being provided with four horny-toothed pads, whichserved in place of the grinders of the living forms. aremore numeious in the manatee, than in the dugongof the Indian HIGH SCHOOL ZOOLOGY. IG-i Ocean (IfaUcore, Fig. 113), but the latter lias tusk-like incisorsin the upper jaw, which are only transitorily present inthe manatee. The caudal fin of the latter is by no means soeffective a propelling organ as is that of the dugong, whichcreature is, on the other hand, quite helpless on land. Whilethe skin in the sea-cow was exti-emely thick and hairless, thatof the manatee is covered with stiff bristles, which are bothfewer in number and shorter in the dugong. Some fossil. Fig. 113.—Duffong (Halicore.) ^ members of the order are known, in which both the teeth andthe skeleton of the hind limbs are more completely representedthan in the living Sirenia, but these, instead of uniting thegroup to the Cetacea, rather piove an alliance with the hoofedanimals, to the study of which we now proceed. 23. The remaining orders of Mammalia arrange themselvesnaturally in two series, the Hoofed Animals (Ungulata) on theone hand, those provided with claws and nails on the other(Unguiculata). Although, at first sight, this distinction appeai-sto be of little importance, the hoof being a horny covering forthe whole of the distal joint of a toe, while the claw or nail ismerely developed on one surface (the anterior), yet it is themark of a difference of function which is associated with someof the most characteristic peculiarities of the Ungulata. In byfar the greater number of the living hoofed animals the extr
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectzoology, bookyear1889
