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Show 1882.] PROF. ST.-GEORGE MIVART ON THE ALUROIDEA. 509 A large Peyer's patch extends down to the ilio-caecal valve; and there are glands at the caecum's apex. In a dried specimen I find the caecum with a rounded dilatation at its end ; but this is probably an artificial distortion. In Hemigalea I found the caecum to be of about the same size as in the Genet, but with strong ineffaceable internal folds, which meet at the apex around a small glandular rosette of about six glands, each gland being about the size of a pin's head. In Galidia the caecum is long, rather slender, and exceedingly pointed towards its apex. In Cynictis it is very long (compared with the other iEluroids), rather slender, and a little curved. In Arctictis the caecum all but or quite aborts1. The large and small intestines run on as one longitudinal tube, of equal calibre, independently of it, with long and strong internal longitudinal folds, which are not interrupted at the place where the minute, quite rudimentary caecum is given off. There is no trace of a transverse constriction or valvular structure between the small and the large intestine. In Nandinia, on the contrary, though there is no external indication of a caecum, or change in the gut's diameter, there is a distinct interruption in the internal structure of the alimentary tube at the junction of the small and large intestines. There is, in th,e first place, a transverse valvular fold. On the small-intestine side of this fold there is a large continuous Peyer's patch, while on the other side of it longitudinal ridges begin to appear. These ridges, however, are not nearly so strongly marked as they are in Atctictis. In Proteles the caecum is short, thick, and rounded a. In Hyana the caecum is long, simple, and rather pointed. It is about 8 inches long. In Crocuta3 it is 6 inches long. Cuvier4 gives the proportion in the Hyaenas of the circumference of the small intestine to its length as 1 to 110, and of the large as 1 to 6. He also says5 that the small intestine increases in diameter from the pylorus to the caecum, and that its walls are so thin as to be almost transparent, though those of the Carnivora are generally more or less thick. Meckel6 says that the proportions borne by the small intestine to the large intestine, are in the Cat from 5 to 1 to 6 to 1, in the Genet as 8 to 1, in the Civet as 10 to 1, in the Zibeth as 15 to 1, and in the Hyaena as 5 (or 7) to 1. According to Hunter ('Essays and Observations,' vol. ii. p. 56), the small intestine in the Suricate is -'something more than the whole length of the body of the animal," while the large intestine "is more than half that length." 1 P. Z. S. 1878, p. 142. On the other hand, the caecum may be half an inch lone • see Journal of Asiatic Soc. of Bengal, vol. xv. p. 193. a P. Z. S. 1869, p. 474. 3 P- Z. S. 1879, p. 84, fig. 2. * Lecons d'Anat. Comp. vol. iv. le partie, p. 211. s i. c. p. 236. 6 Anat. Comp. vol. viii. p. 703. |