136 P H I D I A. 



They are carinated on the dorsal region and smooth laterally upon 

 four series on each side. The abdominal scutellae are narrow, two 

 hundred and thirty in number ; the preanal large and entire. The 

 subcaudal scutellae are disposed upon a double series of seventy-one 

 in each. The tail itself is very tapering. 



Ground color above fuscous, with a triple series of black blotches 

 along the back, seventy-eight in number, the sixty-first opposite the 

 anus ; seventeen on the tail. The blotches of the medial series are 

 proportionally very large, quadrangular, longer than broad, covering 

 six rows of scales, and the half of the adjoining rows, embracing lon- 

 gitudinally five or six scales. A narrow light space of one scale exists 

 between each blotch. The adjoining series is composed of much 

 smaller blotches, alternating and covering three rows of scales con- 

 fluent with the middle ones, thus forming a continuous chain on the 

 back, and inclosing entirely the light spaces between the blotches. A 

 series of subcircular or oblong blotches runs conspicuously along the 

 middle of the flanks, on the fourth, fifth, sixth, and seventh rows of 

 scales. These are eighty-eight in number, the seventy-first opposite 

 the anus, and ten along the anterior half of the tail. The five first 

 blotches are elongated, and exhibit a tendency towards forming a vitta 

 or band. From the middle region of the body to the tail, two obsolete 

 series of very small blotches are seen alternating with the series of the 

 flanks, one above and one below. The abdomen is yellowish, unicolor, 

 except a series of blotches on the extremities of the scutellae, extend- 

 ing sometimes to the outer row of scales. 



Log. — A specimen, thirty-five inches in total length, was collected 

 at San Francisco, California. 



Plate VIII, fig. 1, represents Pituopliis catenifer, size of life. 



Fig. 2, is a profile of the head. 



Fig. 3, an upper view of the same. 



Fig. 4, the head, seen from beneath. 



Fig. 5, a front view of the same region. 



Fig. 6, exhibits the shape and number of rows of scales. 



Fig. 7, the vent and surrounding scutellae. 



