16 MR. F. E. BEDDARD ON THE [Jan. 16, 



forward prolongation, which is as long as, or longer than, the 

 posteiior i-egion of the kidney. There is no bieak whatever 

 between these two sections ; and their appearance as regards 

 texture and colour is identical. The thinner anterior part of 

 the kidney may pehaps be a mesonephros, peisistent in these young- 

 forms. On the two sides of the body the two kidneys differed 

 very considerably in dimensions. The right kidney is, as in other 

 Snakes, more advanced than the left kidney, and its anterior end 

 actually passes a trifle beyond the gall-bladder aiid all but reaches 

 the liver. This kidney is altogether 108 mm. long, of which 44 mm. 

 belong to the postei-ior broad region of the gland, the slender 

 anterior portion being thus much the longer. The right-hand 

 kidney is altogether oidy 92 mm. long, and the broader postei'ior 

 region is here the longer of the two sections, measuring as it does 

 48 mm. 



The slender anterior prolongation of each kidney is not, of coui'se, 

 to be confounded with the adrenal body. This latter is plainly 

 distinguishable from the kidney-tissue by its yellow colour and 

 different texture. It lies in the middle section of the. anterior 

 region of the kidney. 



The gonads were not visible in either specimen. But I believe 

 them both to be females. This conclusion was an-ived at owing 

 to the nature of the gonad-ducts. These ducts were of com- 

 paratively large calibre and without the close windings of the 

 male ducts Moreovei- they were prolonged forwai-d in the case 

 of the right- liand one to a point anteiior to the gall-bladder where 

 the duct appeared to end freely. In the region of the anterior 

 portion of the kidnej^ the duct was attached by an evident though 

 narrow mesentery to the substance of the kidney. The actual 

 course of the gonad-duct of tlie right side is shown in the figure 

 annexed (text-fig. 4, p. 17). Anteriorly it lies to the outside of the 

 kidney. At the junction between the anterior more slender and 

 the posterior stouter region of the kidney it crosses over and lies 

 to the inside of the kidney. 



The diameter of this tube appears to me to be too great to allow 

 of its being identified with the sperm-duct. Another and, as I 

 believe, very strong reason forbids this identification. To the 

 inside of each kidney, along the anterior thinner region of that 

 organ only, is a more slender duct than the gonad-duct, which, 

 however, pi-esents the same general appearance. This duct com- 

 mences some way in front of each kidney, but the exact mode of 

 its commencement I have been unable to ascertain. It follows 

 the kidney fairly closely, lying on the opposite side to that occupied 

 by the gonad-duct, to a point some little way in front of the 

 junction between the anterior and posterior sections of the gland, 

 and there gradually disappears. It seems to me that this structure 

 must be unquestionably homologised with the mesonejjhiic duct ; 

 and if so, the gonad-duct can hardly be the sperm-duct. That it 

 is the mesonephi'ic duct seems to be necessary from the impossi- 

 bility of identifying it with anything else ; and if so, then the 



