. A manual of zoology. Zoology. ir. VERTEBRATA: MAMMALIA, CHIROPTEBA. 637 Fig. 661—Skull of Son'.c (From Ludwig-Leunis.) the rudimentary condition or occasional absence of the canines {Talpa |}-|t. ni'iny shrews f-?, j|). There is great variability in the matter of replacement of teeth; in the shrews,, for instance, the milk dentition is snpjiressed and tlie second only is functional, while in the hedgehog one incisor and one pre- molar in each jaw, a second jiremolar and the canine of the lower jaw func- tion in both dentitions. In many re- spects the insectivores resemble the rodents: a clav
. A manual of zoology. Zoology. ir. VERTEBRATA: MAMMALIA, CHIROPTEBA. 637 Fig. 661—Skull of Son'.c (From Ludwig-Leunis.) the rudimentary condition or occasional absence of the canines {Talpa |}-|t. ni'iny shrews f-?, j|). There is great variability in the matter of replacement of teeth; in the shrews,, for instance, the milk dentition is snpjiressed and tlie second only is functional, while in the hedgehog one incisor and one pre- molar in each jaw, a second jiremolar and the canine of the lower jaw func- tion in both dentitions. In many re- spects the insectivores resemble the rodents: a clavicle is present; there are usually five toes furnished with claws; there is a uterus bicornis, often divided its whole length, and discoidal jjlacenta. Aside from the proboscis-like snout the insectivores resemble the rodents in appearance, forming parallel groups to those of that order. The , or hedgehogs, of the Old World are spined like the porcu- pines ; the SoRiciD^, or shrews {8orex* Blai-ina*), are mouse-like, as are the allied Talpid^, or moles (Scalops,* Comlylura,* star-nosed mole), which burrow in the earth and have the eyes more or less rudimentary. Some authors place here Oaleopitltecus of the East Indies, which has a similar membrane and similar sailing powers as the tlying squirrels. It also presents resemblance to the bats and to the lemurs. The earliest known insectivores date from the Fig. 662.—Skeleton ot bat. (After Brehm.) Order III. Chiroptera. The bats are the only mammals which actually fly, and this at once characterizes them. The flying membrane (patagium) is a thin fold of skin, richly supplied with nerves, which begins at the. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Hertwig, Richard, 1850-1937; Kingsley, J. S. (John Sterling), 1854-1929. New York, H.
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectzoology, bookyear1902
