2 University of Michigan 



frontals, each half the length of the frontal, smaller than the 

 frontoparietals ; parietals almost as wide as the interparietal ; 

 four supraorbitals; two f renoorbitals ; six upper, five lower 

 labials; one anterior chin shield, followed by three pairs, the 

 sides of the anterior two pairs in contact, the posterior pair 

 much smaller, separated by a group of three small scales, and 

 bordered behind by a row of enlarged scales which are sepa- 

 rated by several smaller scales ; a series of granules across the 

 throat from ear to ear ; scales from eye to shoulder very rough, 

 almost tubercular; scales on the throat narrower and more 

 pointed than the ventrals; ventrals strongly keeled, mucro- 

 nate; anal plates five; scales around the middle of body 23; 

 scales from occiput to base of tail 31 ; scales from chin granules 

 to vent 33. 



Snout to vent 32 mm. ; snout to ear 7 mm. ; snout to eye 



3 mm. ; greatest width of head 5 mm. 



Color in life : head and tail deep brown, almost black ; a 

 stripe of reddish brown from occiput to tail, becoming lighter 

 on the sides, where it is bordered by a dark brown stripe ; 

 below reddish yellow; three light spots on upper lip and five 

 black spots on lower lip. 



Remarks : There are nine paratypes of the new species in 

 the collection which vary little in color and scalation. It 

 should be noted that the smallest specimen has a deep groove 

 down the center of the frontonasal, but it is not actually 

 divided. The scale counts of eight specimens average : around 

 the middle of the body 241^, from occiput to base of tail 32, 

 and from the chin granules to vent 34. The main variation 

 is in the arrangement of the chin shields. The third pair 

 may be separated by one, or as in the type, by three small 

 scales bordered behind by scales of equal size, or by a larger 

 scale which may be bordered behind by two scales of the same 

 size with still smaller ones behind, or the smaller, irregular 

 scales may be in direct contact with the larger scale. 



The ]\Iuseum of Comparative Zoology has sent us for com- 

 parison a Leposoma (collected at Suretka, Sixaola River, 

 Costa Rica, by E. R. Dunn) that corresponds fairly well with 



