260 PROCEEDINGS OF THE ACADEMY OF 



in having the seventh superior labial larger than the sixth, and in having 

 four large temporals on each side, of equal size, one smaller above the last 

 labial, and two still smaller at the end of each occipital. The breadth of the 

 head at the temples is equal to the length from the muzzle to the extremity 

 of the occipital suture. Tbere are forty-five black rings on the body and tail, 

 which leave white interspaces, wider upon the back than the flanks. Only 

 the white scales on the latter region are tipped with black. The anal scute 

 is divided. 

 One specimen. Honduras, Dr. S. W. Woodhouse. 



Pseudoboa Schneider. Type P. coronata. 



Hist. Amphib. Fasc. ii. p. 286, 1801. Scytale Boie, Isis, 1826, 981, (not of 

 Merrem.) Wagler, Natur. Syst. 187. Dum. & Bibr. vii. p. 996. Giinther, 

 Cat. Brit. Mus. 187. Olisthenes, Cope, Proc. Acad. Nat. Sci. 1859, p. 296. 



Schneider's name for this genus possesses the right of priority over that of 

 Merrem. The almost universal acceptation of the latter by herpetologists, is 

 also the more to be regretted as the type is not known. The relative num- 

 ber of the gastro- and urosteges in the Scytale anguiformis of Merrem 

 renders its identity with Erythrolamprus venustissimus very improb- 

 able. 



137. P. coronata Schneider. Scytale coronatum Boie. Wagler, Dum. & 

 Bibr. Giinther, etc. Lycodon cloelia, var. Schl. 



One specimen. Caraccas, Mr. W. G. Bolton. 



One " Panama, Drs. Gallaer and LeConte. 



138. P. Neuwiedi nobis. Dum. &Bibr., vii. p, 1001, Olisthenes enphaeus 

 Cope, 1. c. 



One specimen. S. America, Ed. D. Cope. 



Oxyropus Wagler. Type 0. petolarius. 

 Natur. Syst. Amphib., 1830, p, 185. Hqdroscopus et Deiropeda Fitz. Syst. 

 Rept. 1843, p. 26, Brachyruton Dum. & Bibr. vii. p. 1004, 1854. 



139. O. plumbeus Gthr. Coluber plumbeus Wied. Abbild. xii. pi. 6. 

 Duberria (1824) et Hydroscopus (1843) plumbeus Fitz. Brachyruton plumbeum, 

 D. et B. 



One specimen. Cayenne, Gard. plants in ex. 



One " Surinam, Dr. Hering. 



One " ? Dr. Wilson. 



One " Trinidad, Dr. Watson. 



140. O. melanocrotaphus nobis This serpent resembles the O. 

 cloelia, but may be distinguished from it, first, by the form of the head 

 and the distribution of colors on it (second), and third, by the relative 

 length of the tail. 



The profile of the muzzle is very rounding and obtuse, and its sides nearly 

 plane ; the head is deep. Eight upper labial plates, third, fourth and fifth, 

 entering the orbit. Loreal large, as high as long. Anterior border of the 

 vertical plate not greater than the length of the lateral borders. The latter 

 are slightly concave, and scarcely or not at all convergent. Three temporals 

 on the exterior border, the first twice as large as the second, and bounding 

 the sixth and seventh upper labials. Preocular large ; one narrow postocular, 

 which will probably be found to be divided in other specimens. Inferior 

 labials eight. Geneials two pair, broad. Scales in nineteen longitudinal 

 rows. Gastrosteges 161, one entire anal, urosteges 45. Total length 25 in. 

 9 lines. Tail 4 in. 1 1., less than one sixth of total length ; in c 1 o e 1 i a it is 

 a little more than one fifth. 



Coloration. The whole upper surface of the body and tail is of a pale yel- 

 lowish or brownish gray, many scales with one or two borders pure white. 



[June, 



