324 Annals of the Carnegie Museum. 



having twenty-one to twenty-five scale-rows. This character is 

 decidedly of little value in differentiating the two supposed species. 

 Of still less value is the comparative length of the anterior and pos- 

 terior chin-shields. 



Comparative Length of Anterior and Posterior Chin-Shields. 



t Anterior Chin- 



I shields the Chm-shields 



I Longer. E<l"a'- 



Posterior Chin- 

 shields the 

 Longer. 



Specimens with twenty-one to twenty- 

 five scale-rows (43) 7 (16%) j 22 (51 %) 



Specimens with nineteen scale-rows (26 J 6(23%) ' 17(65%) 



14(33%) 

 3 (12%) 



The shape of the loreal of the specimens with twenty-one to twenty- 

 five scale-rows agrees well with the diagnosis of L. albofusca; but the 

 loreal of the specimens having nineteen scale-rows is almost as often 

 longer than deep as deeper than long. 



Shape of Lorfal. 



Longer Than I As Deep as Deeper Than 



Deep. Long, Long. 



Specimens with twenty-one to twenty- 

 five scale-rows (42) 26 (62 %) 



Specimens with nineteen scale-rows (25) 6(24%) 



13(31%) ■ 3 (7%) 

 11(44%) 8(32%) 



The counts of the gastrosteges and urosteges which I have made 

 extend the limits of numerical variation of these characters, and also 

 serve to bring the snakes having seventeen to nineteen and those 

 having twenty-one to twenty-five rows nearer to the same extremes. 

 They are therefore of little value for specific differentiation. 



Number of G.\strosteges and Urosteges. 



Gastrosteges Urosteges. 



Specimens with twenty-one to twenty-five scale-rows (43) . . 164-205 68-98 



Specimens with nineteen scale-rows (26) 170-203 73-95 



The lateral spots vary to the same degree in both classes- of specimens, 

 making it impossible to use this character for diagnostic purposes. 



If the distributional areas of the supposed species were separate 

 such differences as appear to exist might mean a good deal, but the 

 area of L. annulata is much more limited than, and entirely within, 

 that of L. albofusca. 



As there seems to be no combination of characters which definitely 



