1883.] NATURAL SCIENCES OF PHILADELPHIA. 13 



Crotalus confluentus Say. 



Typical variety from near tlie southern end of the Socorro 

 Mountain, five miles from Socorro. 

 Crotalus lepidus Kennicott. 



Prof. Snow was fortunate enough to obtain the first entire 

 specimen of this species, it having been described by Kennicott 

 from two heads. We are thus made acquainted with the most 

 peculiar of the North American rattlesnakes. I proposed for it 

 the genus Haploaspis on account of the undivided nasal plates of 

 the typical specimens. In the present specimen, that plate is 

 divided below the nostril. It is therefore probable that this 

 generic name should be abandoned. 



Mr. Kennicott has well described the scutellation of the head. 

 It may be summarized here by saying that the top of the muzzle 

 is covered by eight smooth scuta ; that the rostral plate is rather 

 low, and is in contact with the prenasal ; that there are two pre- 

 oculars and two loreals ; and that but two scales separate the 

 orbit from the superior labial scuta. Of the latter there are 

 twelve. Occipital scales smooth. Scales of bod}^ in twenty-three 

 rows, the two external on each side smooth. Urosteges, 153; 

 gastrosteges, 2t. The rattle consists of seven segments and a 

 button, and narrows gradually towards the extremity. 



The color above is a greenish gv&^y, which is crossed by nine- 

 teen jet-black rings on the bod}', which do not extend on the 

 abdomen. These rings are two and a half scales wide on the 

 middle line, and narrow downwards on each side so as to cover 

 but one scale in width. The scales which border the annuli are 

 half black and half green, the effect of which is to give the edge 

 of the ring a turreted outline. The edges of the ground-color 

 are paler than any other part of the scales, thus throwing the 

 black into greater relief. A large black spot, shaped like two 

 hearts side by side, with the apices posterior, marks the nape; 

 and^ there is an irregular small black spot on each side of the 

 occiput. Some black specks between the orbits. No other marks 

 on the head. Near the middle of the gray spaces of the body, 

 some of the scales of many of the rows have black tips. The 

 tail is light brown above, and has a basal broad black, and two 

 other narrow brown annuli. Below dirty white, with closely 

 placed shades of brown. 



