NATURAL SCIENCES OF PHILADELPHIA. 559 



As Wagler's name, Chlorosoma, as applied to this genus, is etymologically 

 untrue, we have followed Dr. Giinther in employing the name which immediately 

 succeeds it in the " Natlirliches Syst." 



186. P. 1 f e r s i i Wagl. 1. c. Herpetodryas Olfersii Schl. Dryophylax Olfersii D. 



k B. One sp. Brazil. ? 



187. P. viridissimus Giinther. Chlorosoma viridissimum Wagl. 1. c. Her- 

 pelodryas viridissimus Schl. Dryophylax viridissimus Dum. & Bibr. 



One sp. Surinam. Dr. Colhoun. 



One sp. Patr. ignot. ? 



188. P. craasifrons nobis. 



Expression slightly homalopsine : the eyes more anterior and vertical, the 

 muzzle shorter, and the labials higher than is usual among tree-snakes. 

 Vertical plate nearly as broad as long ; occipitals broad, rounded. Postoculars 

 two ; preocular not reaching the vertical. Postfrontals broad transversely, 

 inferiorly bordered by the postnasals and third upper labial, suture with the for 

 mer longer. Superior outline of the rostral rounded. Nostril a slit ; nasal3 

 confluent, posterior inferior angle acute. Loreal none. Superior labials eight, 

 all higher than long, except the first and last ; eye over the fourth and fifth, 

 small. One large and three small temporals bound the external border of each 

 occipital. Inferior labials ten or eleven, sixth largest, last two or three very 

 small. Pre-geneials longer than the posterior pair. Scales in nineteen long- 

 itudinal rows, smooth ; gastrosteges undulate near their extremities, obtusely 

 keeled. Gastrosteges 206, one divided anal, urosteges 123. 



Coloration. Above uniform dark green, beneath greenish-white, chin tinged 

 with yellowish. 

 One sp. Cayenne. Gard. of Plants, (as Dryophylax viridissimus) 



In the proportions of the body, this serpent much resembles the P. viridis- 

 simus, but even assuming that the absence of the loreal shield is accidental, 

 the proportions of the head and plates are different from those seen in our 

 specimens of that species, and in the published figures of it. 



Gonyosoma Wagler. Type G. oxycephalum. 



Nat. Syst. Amphib. p. 184, 1830. 



189. G. oxycephalum Wagler. G. viridedo. Descr. etlcon. Amphib. pi. 9. 

 One sp. Java. Dr. W. S. W. Ruschenberger 



This specimen has 27 and 28 rows of scales upon the anterior part of the body. 



Cblorophis Hallow. Type C. heterodermus. 



Proc. Acad. Nat. Sci. Phila. 1857, p. 61. 



Body cylindrical, tail not long ; head rather short, eyes large. Scales smooth, 

 anteriorly in oblique transverse series. Nasals two, nostrils between ; loreal 

 large ; one pre-, two postoculars. Gastrosteges faintly angular ; anal plate 

 entire, urosteges divided. Dentition syncranterian. 



We are inclined to regard the arrangement of the plates upon the muzzle of 

 the specimen from which Dr. Hallowell drew up his diagnosis, as abnormal. 

 Another specimen from Guinea exhibits the plates a3 described. This genus 

 seems to differ from Hapsidophrys Fisch., in having a shorter tail, as well as 

 smooth scales. 



190. C. heterodermus Hallow. 1. c. 



One sp. Gaboon. Dr. A. H. Ford. 



One sp. Guinea. P. B. DuChaillu. 



Liopeltis Fitz. Type L. trie olor. 



Systema Reptilium, 1848, p. 26. 



This genus differs from Chlorophis in having a single nasal plate, more 



I860.] 



