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Show 1877.] ANATOMY OF THE RUMINANTS. 7 The psalterium of Moschus moschiferus differs essentially from any other with which I am acquainted. Prof. Flower has fully described and figured it1, at the same time that he has pointed out how much the specimen in the Museum of the College of Surgeons differs from that the account of which is given by Pallas2. Mr. Flower has kindly permitted me to examine the specimen. The nineteen plicae all belong to the primary cycle without doubt; and as this number is that of the primary together with the secondary folds in most ruminants of the same size, it appears to me that their peculiarity consists in the exaggerated development (to the size of the primary) of the second cycle. These laminae are also peculiarly close to one another at their lines of attachment, which is further in favour of this view. Between some of the folds I have detected lines of papillae ; but their presence is the exception, not the rule. Where the psalterium is large it is sometimes found that longitudinal rows of papillary lines are present at intervals on the primary folds, and even the secondary laminae. These are very conspicuous in Portax picta. In some quadruplicate and in all quinquiplicate psalteria the cycles of smallest laminae are nothing more than rows of papillae. In other quadruplicate psalteria the cycles of the fourth power are developed as true folds without any ultimate lines of papillae. Whether or not this is the case is indicated in Table I. (p. 5) by the descriptive name in column X., whatever the power, being printed in roman letters or italics. When in italics the laminae of the highest power are only represented by papillary rows. The liver is always simple and small, being situated almost entirely on the right side of the median line. The umbilical fissure never extends more than one half through the organ, generally less. The lateral fissures never exist. The gall-bladder is absent in all the Cervidae, according to my observations, and in the genus Cephalophus among the Bovidae. The caudate lobe is very variable in size, and is frequently smaller in adult than in young individuals. In most species it is elongate, slender, and lateral, forming little more than an incomplete cap to the right kidney; in some it is quadrate from the development ventrally of its basal portion. The Spigelian lobe is frequently entirely absent, as such. When present it is a development of the median portion of the posterior margin of the portal fissure, extending so as to overlap it. When its base is broad, as in the Sheep, it may be termed oviform; when it is pedunculate, as is generally the case in the genus Rusa, it may be termed rusiform. Variations of slight degree are found in individuals of the same species. From Table I. (pp. 5, 6) the peculiarities of the different varying parts of the organ in the specimens which I have had the opportunity of examining may be determined (columns II. to V.). ' P. Z. S. 187o, p. 170. ' Spicilegia Zoologica, fasc. xiii. (1779). |