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Show 22 DR. E. LONNBERG ON DIGESTIVE [Jan. 14, As in Trichosurus, the small intestine of Phalanyer is provided with at least one Peyer's patch. It is in the specimen before m e situated 74 cm. from the caecum, and measures 60 m m. in length by 13 in breadth, being composed of a great number oi small nodules. There are, however, probably more than one Peyer's patch normally in the small intestine of the Cuscus, since Cunningham observed no less than nine in his specimen described in the ' Challenger' report. Some of these were, however, a mere speck." The terminal portion of the small intestine shows some longitudinal folds, but these are probably not permanent as they disappear by transverse stretching. The ileo-caecal valve is well developed and protrudes 12 to 14 m m . into the caecum. From this valve extends on both sides a fold-the caeco-colic valve. At the ileo-caecal valve it is about 7 m m . in height, but gradually diminishes; about 1 cm. from the valve it passes into the muscular thickening which forms the caeco-colic sphincter. The communication between the caecum and the colon may thus be completely shut off by means of the incomplete caeco-colic valve and by contraction of the caeco-colic sphincter. When such a shutting-off is effected it seems as if the opening of the ileo-caecal valve would be directed into the caecum, and the function of the above-described caeco-colic valve may partly be to brace the ileo-caecal valve so that it shall not be compressed and closed when the caeco-colic sphincter contracts. But, as it is arranged now, the contents of the small intestine may pass directly into the caecum without risk of slipping down into the colon. On the caecal side of the valve there is an area on which the mucous membrane is provided with a considerable number of small depressions. These are about 1 m m . in diameter, and correspond, no doubt, to the glandular patch with similar depressions which has been described above in the phyllophagous Phalangerids, although the situation is a little different in these latter, in which this patch is found on the colic side of the valve. Cunningham does not mention this glandular patch in his description of the intestine of the Cuscus. The width of the caecum is different at different places. It is at first about 4 cm., then widens to 6 cm., but soon becomes constricted to only 2 | cm., widens again to 5| cm., then it is constricted to 2| cm., and again widened to 4 cm., which condition is once more repeated, and then it finally tapers towards the end, which terminates in a digitiform appendix 2 cm. in length by 4 m m . in thickness. Cunningham 1 has in the same species only observed that the caecum " tapers uniformly." The appendix is hollow and filled with the contents of the caecum. Its walls are thicker than those of the ordinary caecum, and it might be a lymphatic organ, which perhaps might be compared with the one of similar situation in the common rabbit. The caecum of Phalanger is somewhat sacculated by means of i " Report on the Marsupialia," Rep. Scient. Results ' Challenger,' Zoology, pt. xvi. |