1908.] OF SNAKES OF THE GENUS CORALLUS. 151 



In view of the rather slender differences which often exist 

 between different genera among the Ophidia, it appears to me 

 that the differences here recorded between Corcdlus madagas- 

 cariensis and C. cookii are worthy of receiving generic value. 

 But for the present I do not consider the matter of a name 

 for the Madagascar species, since there is no knowledge of the 

 structure of the remaining American species of the genus. 



The following brief statement embodies the principal ana- 

 tomical characters of the two species, Corcdlus viadagascariensis 

 and C. cookii : — 



Corallus madagascariensis. 



Mental groove bordered hy eight scales on each side. Bronchus 

 continued for a considerable distance into larger lung. Intercostal 

 arteries regularly paired like those of Python *. No rudiment of 

 umbilical vein. Liver commences closer to apex of hearty of 

 considerable length, terminating in a very long thin posterior 

 prolongation of one lobe. Gall-bladjder close to end of liver. 

 Pancreas with no prolongation to spleen. Kidneys short, nearer 

 to vent. 



Corallus cookii. 



Jlental groove bordered by ten scales on each side. Bronchus 

 continued only for a short distance into interior of larger lung. 

 Intercostal arteries not regularly jxdred like those of Boa. A 

 rudiment of or a more fully -developied, umbilical vein. Liver com- 

 mences further from apex of heart, of less considerable length, 

 sometimes terminating in a short thin prolongation of one lobe. 

 Gall-bladder at a considerable distance from end of liver. Pancreas 

 with a prolongation to spleen. Kidneys longer, further from vent. 



For the measurements made above for the purpose of con- 

 trasting the two species of Corallus, I was compelled to select one 

 of the larger specimens of Corallus cookii dissected by myself. 

 For though I have dissected smaller examples of the same length 

 as the individual of Corallus madagascariensis, the details as to 

 the position of the viscera Avere unfortunately imperfect in my 

 notes. From such details as I have 23reserved, however, it would 

 not ajapear that much has been lost by not being able to make a 

 more accurate comparison between the two species of snake in 

 these particulars. Since the examples of Corcdhts cookii which 

 I have examined range from a length of 48| inches to 71 inches, 

 it becomes a matter of interest to note what, if any, alterations 

 take place in the relative sizes of the various organs and their 

 position with regard to each other during the process of gi^owth. 

 There is, furthermore, another rather important variation to be 

 deduced from these studies, as will be apparent when the facts 



* E\c. Pi/tJion spilotes (see above, p. 143). 



