336 PROCEEDINGS OF THE ACADEMY OF 



but narrows abruptly at one-tbird its lengtb from the base. Dorsal rowt; 

 twenty-one, all distinctly carinate. The scales are rather broad, and much 

 rounded posteriorly, those of the first dorsal row disproportionately small. The 

 head is elongate and rather narrow posteriorly, but very deep and hut little 

 depressed on the snout. All the plates of the crown are large ; the vertical 

 very hroad and short, the loral longer than high, the upper and lower postor- 

 bitals small, but the central elongated so as to reach the labial plates. 



In pattern of coloration and structure, this species departs somewhat from 

 the usual style of the genus. The ground color is light olive brown, crossed 

 on the anterior half of the body by waving or somewhat zigzag transverse black 

 bands, covering two or three scales longitudinally, and separated by intervals 

 of one or two scales. These bands do not taper regularly on the sides as in N. 

 s i p e d o n , but are constricted upon about the sixth row on each side, but 

 are as wide upon the third, as on the vertebral row. Posteriorly these bands 

 become narrower, and finally break up into a dorsal series of vertically elon- 

 gated spots, and a lateral series of small circular ones, which do not alternate 

 with the dorsal series as inN. sipedon, taxispilotus and others. 

 For two inches behind the head, the transverse bands are replaced by four 

 distinct longitudinal black lines, the lateral ones each covering the third, 

 fourth, and part of the second rows, the upper ones covering the seventh, eighth, 

 ninth and part of the tenth rows ; these black lines are separated by a little 

 over one scale of ground color. None of the black markings involve the first 

 dorsalrow, which is yellowish olive, excepting some irregular dark mottlings. 

 The head is yellowish olive, with the middle of the occipitals and verticals 

 black, and a black patch extending from the eye back above the labials. The 

 rostral is yellow, distinctly margined above with black. All the labials above 

 and below, and the inframaxiliary plates are yellow, prominently margined 

 with black. The abdomen is yellow, with two lines of black blotches. 



1348, Tampa Bay, Florida. Mr. D. Welch. 



HETERODON Pal. de Beauvois. 



H. Kennerlvi Kennicott. 



Spec. char. Head broad, very short anteriorly. Rostral plate very large. 

 Loral plate very small, sometimes absent. Only two supplemental plates be- 

 hind the azygas ; the latter is sometimes replaced by two symmetrical con- 

 tiguous plates, and without any supplemental. The prenasal and prefontal 

 in contact with the posterior process of the rostral. Dorsal row of scales 

 twenty-three, all carinated except the first and second, which are perfectly 

 smooth. Ground color light yellowish grey ; a dorsal series of rather indis- 

 tinct rounded or subquadrate brown blotches ; a second series of smaller cir- 

 cular spots, much darker and more distinct ; below this a third, and more 

 indistinct series. 



Descr. In its general form and appearance this resembles the H. nasicus, 

 with which it is sometimes found associated. The body, however, is rather 

 shorter and thicker than in H. nasicus, and the head is broader with the 

 part of the head anterior to the eye decidedly shorter. The nasals are not as 

 well developed longitudinally as in H. nasicus, but the result of this 

 shortness of the anterior part of the head is seen in the very small loral which 

 is frequently wanting entirely. There is never more than one loral while 

 frequently two are seen in H. n a s i c u s , in which the loral is in every case 

 strikingly larger than in Kennerlyii. The most striking difference be- 

 tween these species is in the number of small plates surrounding the azygos, 

 or postrostral. While in H. nasi cu s there are always at least ten of these, 

 one or two of which margin the inner edges of the prenasals and prefrontals, 

 there are never more than two, and frequently but one additional plate in H. 

 Kennerlyii, and the prenasal and prefrontal are always in contact with 

 the posterior process of the rostral. The azygos is short, nearly as broad as 



[Aug. 



