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



Another apparent difference I mention, although I have only 

 noted it in one specimen of each of the two species under consider- 

 ation, as it could hardly be ascertained in the case of the newly-born 

 young. This fact concerns the gall-bladder. In Eunectes oiotceus 

 the gall-bladder gives rise to two ducts lying side by side and arising 

 independently from the bladder. These branch and anastomose in 

 a moderate way with each other and with the hepatic duct. The 

 latter is single, but in the neighbourhood of its junction with the 

 cystic ducts it gives off twigs which form a network alongside of the 

 mainductwhich is obvious as such. Threeducts pierce the pancreas 

 ontheirway to open into thegut. In U. murim(,s, on the other hand, 

 four cystic ducts arise from the bladder and form in the same way 

 but a slight rete. There are, however, two distinct hepatic ducts 

 running side by side from the liver. Three of the cystic ducts join 

 almost immediately to form a single duct, so that the difference 

 from E. 'iiotceus is not so very mai-ked. 



In showing difference in the structure of the pancreas between 

 different species this genus is like Python, where the discrete 

 multilobate pancreas of '' P. hivittatus " * contrasts with that of 

 some other species. 



Resume. 



It may be convenient to briefly recapitulate the main facts 

 in the foregoing pages. 



(1) The young of Eunectes notceus are produced alive and with 

 considerable remains of the j^olk-sac. 



(2) They possess a mesonephros quite continuous with the 

 kidney, and (female) a mesonephric duct extending along the 

 greater part of the mesonephros and reaching beyond it anteriorly. 



(3) The umbilical vein of the newly-born young persists in the 

 adult [Eunectes murinus) and is quite independent of the 

 anterior abdominals. 



(4) The anal " claws " in Ettnectes notceus (and in some other 

 Boidae) offer distinct sexual characters, differing in form in the 

 two sexes. These characters are recognisable in the newly-born 

 young. 



(5) The suprarenal portal vessels open into a continuous 

 slender trvink running along the mesonephros and ending on the 

 kidne}^ posteriorly. Their "portal" character is thus secondary. 



(6) The vessels which collect blood from the parietes and join 

 the portal systems, whether of the liver, kidneys, or suprarenal 

 bodies, are maiidy, and in the case of the liver exclusively, affluents 

 of the left-hand system of veins and arise exclusively or almost so 

 from the left parietes. 



(7) Both the liver and the left kidney are supplied from a 

 continuous longitudinal parietal vessel which receives the branches 

 from the body- wall and transmits the blood by a series of blanches 

 to the portal vein or to a longitudinal vein connected with the 



* See fig. in Broiin's Thierreich, Bd. vi. Abtb. iii. pi. cxxsii. fig. 6 (copied from 

 Poelman). The identity of the species seems uncertain. 



