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Show 418 ON THE ANATOMY OF SUS SALVANIUS. [Julie 19, which runs up almost to the middle line, and called the processus superior ; it then bends downwards and forwards, this portion being called the processus anterior (ssa), and is continued forward as the diagonal fissure (d). On the left side the suprasylvian fissure is more simple (figs. 2 and 3) : it has two posterior branches and an ascending anterior branch as on the right side ; it then passes downwards and forwards and terminates. The diagonal fissure (d) is quite separate on this side from the suprasylvian fissure. Between the suprasylvian fissure (ss) and the longitudinal fissure is a straight fissure, fis. lateralis (I) (fig. 3). A little anterior to the processus superior of the suprasylvian fissure springs the fis. coronalis (co) (fig. 3), an important fissure, which runs from the longitudinal fissure and extends forwards and outwards till it nearly meets the rhinal fissure. Besides these principal fissures there are a few of small size present, especially on the right side. A very small speck of the island of Reil is to be seen at the junction of the rhinal and sylvian fissures on each side. The olfactory bulb is of considerable size. In general form and in the arrangements of the fissures the brain is exceedingly like that of Sus, especially on the left side. The uterus was seen, on opening the abdominal cavity, to occupy the anterior portion ; and on examination was found to be pregnant, containing five young. It resembles that of the Pig. The kidneys measure 5*5 cm. in length, and are surmounted by suprarenal capsules of considerable size. Conclusions.-The differences found to exist between the animal just described and Sus scrofa are very unimportant and few, the chief being the absence in the present specimen of the transverse fold between the gastric cavity and the antrum pyloricum, and of the long Peyer's patch in the intestine, and the presence in the liver of a superficial vena cava, of a small cystic fissure, and its right lateral lobe being considerably larger than the left. Those differences are not sufficient to require the formation of a distinct genus for the animal as has been done by Hodgson, who claims for it tbe following generic characters as separating it from Sus:-a difference of dentition, since in tbe specimens examined by him the posterior molar was absent, indicating probably that it was the skull of a young animal, and that the tooth had not been acquired (this supposed difference of the molar dentition from that of Sus, I have shown does not hold good) ; the canines not being protruded beyond the lips (a condition which we find to obtain in the male specimen now living in the Gardens); the inner digit being shorter than the outermost (a condition which we find obtains in Sus scrofa). Having shown that none of these supposed generic characters exist, and that the animal resembles Sus so closely that there is no ground for separating it from that genus, the generic name Porcula, by which it has been known since Hodgson first described it, must be abandoned unless hitherto unobserved or at least unrecorded differences should present themselves in the organs yet to be examined which would justify the retention of the name. |