PITUOPHIS. G9 



tionally small, in 33-35 rows, the 7 outer ones perfectly smoolh and 

 somewhat larger than the remaining rows. 



Ground-color yellowish brown, with three series of dorsal black 

 blotches, 53 in number, from the head to opposite the anus, with 

 12 on the tail, in the shape of transverse bars. Those of the 

 medial series the larger, and covering 8 or 9 rows of scales. On 

 the anterior part of the body they arc subcircular, embracing longi- 

 tudinally four scales ; posteriorly they become shorter by one scale. 

 The light spaces between are a little narrower than the blotches 

 themselves for the twelve anterior blotches, and wider than the 

 blotches for the remaining length of the body. The blotches of the 

 adjoining series alternate with those of the medial series, being oppo- 

 site to the light intermediate spaces, across which the blotches of 

 either sides are generally united by a transversal narrow band. The 

 flanks are densely covered with small and irregular blotches, forming 

 three indistict series, confluent in vertical bars towards the origin of 

 the tail. Inferior surface of the head yellowish, unicolor. Abdo- 

 men dull yellow, with crowded brownish black blotches in series on 

 the extremity of the scutella3. 



Red River, Ark. 231. 52. 35. 38i. 4|. Capts. Marcy&McClellan. 

 « 231. 52. 33. 24^. 2J. " 



4* Pituopliis catenifer, B. & G.— Head subelliptical, flattened 

 above. Vertical plate elongated, nearly equilateral, posterior triangular 

 portion excepted. P^ostral broad. Anteorbitals 2 ; postorbitals 3. Loral 

 trapezoidal, proportionally larger than in other species. Dorsal rows of 

 scales 31 ; the 4 external rows smooth. Tail forming about j of the total 

 length. Frontal black bar conspicuous. Postocular vitta of a jet black, 

 reaching the angle of the mouth between the penultimate and last upper 

 labials. Color of body grayish yellow, the triple series of dorsal black 

 blotches, 61 in number, from the head to the origin of the tail, forming a 

 continuous chain all along the back, owing to the confluence of the lateral 

 series of small blotches with the large medial series, with which they alter- 

 nate. A series of proportionally large subcircular blotches along the mid- 

 dle of the flanks. Middle of the abdomen unicolor, with an external scries 

 of black spots on each side. 



Syn. Coluber catenifer, Blainv. Nouv. Ann. Mus. Hist. Nat. Ill, 1834. 

 n. xxvi. figs. 2, 2 a, 2 b. 



Head subelliptical. Vertical plate maintaining its width posteri* 

 orly. Superciliaries proportionally large. Occipitals very much 



