32 MR. F. a. BEDDARD OX THE [Jan. 16, 



It measures 19| inches in length. 



The base of the heart lies 4| inches from the tip of the snout. 

 The liver, which is 7 inches long, commences just at the heart as 

 in Vipers. The gall-bladder lies 14 inches behind the tip of 

 the snout. The kidneys are elongated, and not particularly- 

 shortened as in Ur^/x. The right kidney, 23 mm. long, ends 

 21 mm. in front of cloaca. The left kidney, 21 mm. long, ends 

 11 mm. in front of cloaca. The right testis begins 10 mm. behind 

 the gall-bladder ; the left testis begins 9 mm. behind end of right 

 testis. 



The lung of Rysia is single *, and the vascular part, which is 

 of considerable thickness, extends for a considerable way down 

 the liver, being some 2^ inches in length. The windpipe, as is 

 usual, is formed of incomplete rings, a fibrous fold connecting 

 them along its entire length. Just before the trachea opens into 

 the lung there is a minute orifice which represents the 2nd 

 bronchus ; but there is no approximation to an equality between 

 the two bronchi such as exists in the Boine snakes. The end of 

 the trachea, that is, of course, of the only functional bronchus, 

 extends some little way into the lung before it disappears. This 

 disappearance is not quite abrupt ; the rings of the bronchus 

 cease just before the end to be circular, transversely-arranged 

 cartilages ; they anastomose with each other, and finally assume 

 a honeycomb disposition, precisely like the lining-membrane of 

 the ensuing lung. Still the bronchial region can be distinguished 

 from the pulmonary by its bluish colour. 



Alimentary Canal. — The condition of preservation of the spe- 

 cimen which I have dissected, and the comparatively empty 

 alimentary canal, render it possible to give an accurate account of 

 the rugte and plications of the different regions, which is not 

 always so easy. There ai-e, moreover, obvious diflerences between 

 Ilysia and some other snakes, both in the structure and pro- 

 portions of the several regions of the alimentary tube. The 

 oesophagus extends to the posterior end of the liver, where it more 

 or less suddenly passes into the stomach. Internally the demai^- 

 cation is quite abrupt. It is shown, in fact, by the different 

 nature of the folds of mucous membrane which line the two 

 sections of the anterior part of the alimentary canal. The 

 stomach in its anterior pait is lined by thi'ee, and three only, thick 

 longitudinally- running folds. At the junction of stomach and 

 cesophagus these thick folds disappear as such, and are either 

 nearly or quite continuous, with at least six similar but much 

 smaller folds. There is thus a perfectly obvious demarcation 

 between oesophagus and stomach. The stomach itself is 56 mm. 

 (or about 2 inches) long, and is plainly di^dsible into two regions : 

 the first of these is much the larger and measures 48 mm. ; the 

 second is about coextensive with the gall-bladder, which is attached 

 to it and measures 8 mm. The larger anterior region of the 



* As Mr. Butler (P. Z. S. 1895, p. 704) and others Lave noted. 



