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Show 1882.] PROF. ST.-GEORGE MIVART ON THE ALUROIDEA. 465 The length from the atlas to the end of the sacrum being taken as 100, the relatively longest skulls thus measured have the proportions of 29*5 (Cynogale) and 28*9 (Genetta). Tbe shortest has 19*8 (Leopard). The shortest Viverrine are 21*4 (Viverra civetta) and 21 * 9 ( Cryptoprocta). The greatest width between the outsides of the zygomata is 22"*0 (Tiger). The broadest non-feline skull at the zygomata is 18"*3 (Crocuta); and the broadest Viverrine skulls are 7"'3 (Viverra civetta) and 7"'0 (Cryptoprocta). The greatest widths of the zygomata in proportion to the spine at 100 are 24*4 (Suricata), 21*5 (Lion), and 21*2 (Crocuta). The shortest is 10*5 (Eupleres). The length of the skull from basion to praemaxilla being taken as 100, the (relatively) broadest zygomatic arches measured across are 89*4 (Suricata) and 89*3 (Felis), the Hyana brunnea being 83*4. The narrowest Felis is 80*4, the narrowest Viverrine (Herpestes) 44*4. I have much desired to find a line to be measured externally as a basicranial axis. The received basicranial axis can only be measured in a vertical longitudinal section, and so can rarely be got at. I should have been well satisfied with a line from the basion to the front end of the praesphenoid or of the basisphenoid, if either of these two latter points were generally determinable externally ; but, unfortunately, such is not the case. I have therefore been compelled to take as a base a line drawn from the basion to a point which may, for convenience, be distinguished as the "ovalion," and which is the middle point of a transverse line joining the hindmost point on the margin of one foramen ovale with that of the other. This base, compared with that of the spine (from the atlas to the end of the sacrum) taken as 100, I never find to be more than 9*0 (Hemigalidia) or less than 4*5 (Felis). Its greatest proportion in Felis is 6*2, its least proportion in the Viverrida is 5*1 (Viverra civetta). In Crocuta it is 6*0, in Proteles 7*3. The base, compared with the total cranial length at 100, has for its highest proportions 31*1 (Galidia), 28*7 (Hemigalidia), and 28*2 (Felis). Its smallest proportion in Felis is 20*5 ; and the smallest of all are Hyana brunnea (211) and Suricata (19*3). If this base be taken as 100, then the greatest relative expansions of the zygomata are 463*6 (Suricata), 400*0 (Felis), and 395*6 (Hyana brunnea). The smallest are 194*4 (Eupleres) and 195*2 (Genetta). The greatest relative breadths of the brain-case, compared with the spine at 100, are 13*8 (Suricata) and 13*3 (Felis). its least breadth 5*9 (Viverra civetta). Its greatest breadths compared with the length of the skull at 100 are 54*5 (Felis) and 50*8 (Suricata); its least proportion is 27*0 (Hyana brunnea). Its greatest breadths compaied with the base taken as 100 are 211*7 (Felis), 263 (Suricata), and 180*0 (Crossarchus); its least proportions thus estimated are 102*7 (Pioteles) and 115*6 (Viverra civetta); the smallest I have found in Felis is 145*4. |