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Show 1882.] PROF. ST.-GEORGE MIVART ON THE ALUROIDEA. 515 bronchi long and narrow in Hyana ; while in Suricata the bronchi are very large, and almost without rings. In Felis, Viverra, Genetta, Hemigalea, Herpestes, Suricata, Proteles, and Hyana the lungs are divided into four lobes on the right side, and into three on the left side. In Crocuta1 the right lung has six lobes and the left lung three. Meckel (/. c. p. 492) says that the two lower left lobes in the Genet form but one, and that in the Tiger, Leopard, and P u m a there are also but two on the left. Great Blood-vessels. In Felis, Viverra, Genetta, Hemigalea, Proteles, and Crocuta the aortic arch gives off one great trunk, whence arise first the right subclavian and then the carotids. The left subclavian is given off separately2. In Felis, Genetta, Prionodon, Hemigalea, Herpestes, and Crocuta? the abdominal aorta does not give off common iliac arteries, but first gives off two large arteries which spring opposite each other from the aorta and are the external iliac arteries, and then continues on for a short space before giving off another pair of vessels (also arising opposite each other), which are the internal iliac arteries. THE BRAIN. In the brain of the Cat, and in the brains of such Felida as I have had the opportunity of seeing, there is a well-marked crucial sulcus, the hinder inner end of which is separated (on the inner surface of each cerebral hemisphere) from the anterior end of the calloso-mar-ginal sulcus by the continuation forwards of the hippocampal gyrus into the superior external gyrus. This condition does not seem to obtain in any non-feline iEluroid. In Genetta the superior lateral gyrus (s) runs simply forwards beside its fellow of the opposite side without being divided by any transversely extending crucial sulcus, the place of which is only indicated by a minute notch on its inner border (c n). Nevertheless the superior lateral gyrus bears a small depression (d) placed a little behind and external to the notch just mentioned ; and this depression m ay represent the outer end of the crucial sulcus of Felis. At its anterior end the superior lateral gyrus dips down, and then becomes in part continuous with the middle lateral gyrus (m) above the upper end of the supraorbital sulcus (o s). The Sylvian fissure (Sf), which is rather long and strongly concave forwards, is bounded on each side by the inferior lateral gyrus, which gyrus is m u c h broader behind than in front of the Sylvian fissure. * The inner side of the anterior end of the superior lateral gyrus (beyond the notch c n) runs backwards, beneath the calloso-marginal sulcus, and becomes continuous with the hippocampal gyrus. From the minute indication of the crucial sulcus (c n) a sulcus runs 1 P.Z.S. 1879, p. 88, fig. 4. 2 Meckel (Anat. Comp. vol. ix. p. 396) appears to have found all four vessels spring from a common trunk in the Genet. :t P. Z. S. 1878, p. 89. |