Most of the CARNIVORA except the Bears and Seals have very long tails, the greatest number of vertebrae, thirty-six, being met with in _Paradoxurus_. Bears have only eight to ten caudal vertebrae. Chevron bones are not often much developed. In INSECTIVORA the tail is very variable as regards length, the number of vertebrae varying from eight in _Centetes_ to forty-three in _Microgale_. In CHIROPTERA the tail is sometimes quite rudimentary, and as in _Pteropus_, composed of a few coalesced vertebrae, sometimes it is formed of a large number of slender vertebrae. In PRIMATES also the tail is very variable. In Man all the four caudal vertebrae are rudimentary and are fused together, forming the _coccyx_. In the Anthropoid apes, too, there are only four or five caudal vertebrae. In many monkeys of both the eastern and western hemispheres the tail is very long, having thirty-three vertebrae in _Ateles_, in which genus it is also prehensile. Chevron bones are present in all Primates with well-developed tails. In the Lemuroidea the number of caudal vertebrae varies from seven to twenty-nine. FOOTNOTES: [145] See W.H. Flower, "Remarks on the homologies and notation of the teeth in Mammalia," _J. Anat. and Physiol. norm. path._, Vol. III., p. 262; R. Owen, _Odontography_, London, 1840--45; C.S. Tomes, _Manual of Dental Anatomy_, London, 1876. See also H.F. Osborn, "Recent researches on succession of teeth in Mammals," _Amer. Natural._, XXVII., p. 493, and "Rise of Mammalia in N. America," _Stud. Biol. Lab. Columb. Coll._, Zool. I., no. 2. [146] See E.B. Poulton, _P.R.S._, Feb. 1888, and _Quart. J. Micr. Sci._, Vol. XXIX. 1889; also Oldfield Thomas, _P.R.S._, XLVI. (1889). [147] W.H. Flower, _Phil. Trans._, vol. 156, pp. 631--641, 1867; also Oldfield Thomas, _Phil. Trans._, pp. 443--462, 1887. [148] C. Röse, _Anat. Anz._ VII., p. 639. [149] W. Kükenthal, _Anat. Anz._ VI., p. 364. [150] See p. 348. [151] W. Leche, _Morph. Jahrb._ XX., pp. 113--142 (1893). [152] E.C. Stirling, _P.Z.S._ 1891, p. 327. [153] O. Thomas, _P.Z.S._, 1895, p. 870. [154] F. Ameghino, _Bull. Ac. Argen._ XII. p. 437. According to H. Burmeister, _Annal. Mus. Buenos Aires_, III. 401 (1891), enamel does not occur, osteodentine having been mistaken for it. [155] E. Ballowitz, _Arch. Mikr. Anat._ XL. p. 133. [156] See Oldfield Thomas, _P.R.S._, vol. XLVII., p. 246 (1890). [157] J. Taeker, "_Fur Kenntniss der Odontogenese bei Ungulaten_." Dorpat, 1892. [158] See p. 345. [159] See p. 345. [160] According to H.F. Osborn, _Amer. Natural._, XXVI. p. 763, a number of not very closely allied forms have been included under _Lophiodon_. [161] C. Earle, _J. Ac. Philad._, vol. IX., 1892, p. 267. [162] _Encyclopaedia Britannica_, article _Mammalia_, p. 424. [163] See T.H. Huxley, "The dental and cranial characters of the Canidae," _P.Z.S._, 1880, p. 238. [164] G.B. Howes, _Journ. of Anat. and Phys._ XXVII., p. 544. CHAPTER XXIII.