| OCR Text |
Show 154 DR. E. LONNBERG ON THE [Feb. 20, The terminal portion of the rectum, perhaps 25 cm., is missing. For comparison it may be mentioned that Mr. J. Arwidson made the following measurements of the intestine of another specimen. He loosened the intestine from the mesentery and stretched it out on the deck of the steamer, which of course resulted in larger figures. Small intestine 31 m. 2 cm. Caecum 75 cm. Large intestine 11 m. 99 cm. But in this case, also, the last part of the rectum from the anterior end of the urinary bladder was missing. Since the intestine was stretched in this case, it may be more reliable to use my own figures. W e find, then, that the small intestine is not much more than twice as long (more exactly 2*1, and according to Arwidson's measurements 2*5) as the large intestine. For comparison I have in the same way measured the intestines of a sheep and a goat preserved in formalin and still adherent to the mesentery, viz.:- Ovis. Capra. Small intestine 15 m. 15 cm. 14 m. 77 cm. Caecum 36 cm. 22 cm. Large intestine .... 4 m. 90 cm. 4 m. 90 cm. In both these cases we find that the small intestine is fully three times as long as the large. Similar figures occur in literature concerning other species of Ovis and Capra, and in Bos the small intestine is 3 to 4 times as long as the large one. The great length of the large intestine in the Musk-ox is an adaptation suitable for the digestion of some special kind of food. It is thus probable that feeding on the twigs of the arctic willow and similar indigestible material, which, when the short arctic summer has passed, must be the only food of this hardy animal, has produced this great development of the large intestine. The liver of the Musk-ox (fig. 8, p. 155) is divided into a right and a left lobe. The diameters of the left lobe are 16 cm. x 21 cm., and its thickness is between 4 and 5 cm. The corresponding measurements of the right lobe are 18, 22, and 8 cm. The spigelian lobe is small and triangular (4^ cm. base, 2| height) with a broad base, thus exhibiting that shape which has been called by Garrod1 oviform. The lobus caudatus (I.e.) is flattened, 12| cm. long by 8± broad, and carries at the end a small lobule 3-3 cm. broad and 1*8 long. The gall-bladder (gb) is, as usual, situated on the posterior surface of the right lobe, 9 cm. from the umbilical fissure, the depth of which is about 6 cm. It has thus a rather central position in the right lobe. When empty and contracted it is 11 cm. in length. The ductus choledechus, which has a considerable width, opens into the duodenum 63 cm. from the pylorus. About 10 cm. before it pierces the wall of the intestine it receives the ductus pancreaticus (cf. the figure). This description being taken from the organ of a full-grown bull. A comparison of the liver of Ovibos with that of other Pecora ' Proc. Zool. Soc. 1877, pp. 2 et seq. |
