346 BULLETIN 17 7, UNITED STATES NATIONAL MUSEUM 



Color: Above pale gray-brown, each scale powdered with many 

 minute brown dots; a dorsal series of arrow-shaped brown markings 

 distinct on the anterior portion of the body, but becoming indistinct 

 posteriorly; head with an elongate brown median stripe; numerous 

 other brown spots on the snout, supraorbital region and parietals; a 

 white stripe commencing on the loreal region and continuing back- 

 wards upon the upper portion of the supralabials, widening on the 

 neck and continuing for a very short distance on the body on the 

 second and third scale rows before it becomes indistinct. Entire chin 

 and lower portion of supralabials dark brown, with a few large white 

 spots on the infralabials and on the chin shields. Ventral surface gray- 

 brown, with numerous small brown dots on each ventral plate, particu- 

 larly congregated at its posterior border as well as at the sides and on 

 the lowest scale row, so that a more or less distinct lateral stripe is 

 visible; tail light gray beneath, darker above, spotted all over with 

 small brown clots. 



Variations. — The range for ventrals in this species is given as 166 

 to 177, and for subcaudals 72 to 88 by Boulenger. It has been found 

 that higher limits for both are possible, as Fischer had a snake from 

 Port-au-Prince with 182 ventrals, while U.S.N.M. No. 10165, from 

 the same locality, has 92 subcaudals. The scale rows are 19 invari- 

 ably; the upper labials are usually 8, and the lower labials 9 or 10. 



The loreal plate is small in this species in proportion to the other 

 head scales. Except for the absence of the loreal, Cope's unique 

 specimen of scalaris is indistinguishable from Giinther's ferox. When 

 the loreal is already so small in comparison to other head plates, its 

 complete absence now and then is of no significance and does not 

 warrant any specific separation. The frontal is usually equal to its 

 distance from the end of the snout, though occasionally a little longer. 



The variation in intensity of color must be rather great, as No. 69433 

 is a very dark purplish brown, on which no markings show except the 

 light streak on the sides of the head and neck. The young specimen 

 No. 10166, on the contrary, has every marking very distinct, while 

 anteriorly on the sides additional rectangular blotches are visible 

 above the light stripe, and below it on every second or third scale 

 of the first scale row is a dark brown irregular spot. 



Specimens examined. — As listed in table 67. 



