1848.] 



61 



the nasal ; the nostril, the greater part of which is in the fronto-nasal, occu- 

 pies the fronto-nasal suture; the anterior frontal is a well defined plate lying 

 innnnediately posterior to the rostral, and in contact also in front with the 

 fronto nasal plates, this portion being excavated to receive the corresponding por- 

 tion of the latter; it is convex upon its posterior border, where it is in con- 

 tact with the posterior frontal and the supraocular, the latter being exterior to 

 it, and also to the fronto-nasal ; the preocular is triangular in form, its widest 

 part being downward, lying in front of the ocular and in contact with the supra- 

 ocular; the eye, which is snnall, but distinct, is placed in the angle fornned by 

 those two plates; the ocularis large, convex upon its posterior border ; it is 

 in contact above where it fo'msan acute angle, with the inter-parietal superiorly 

 with the supra-ocular, anteriorly with the preocular, and inferiorly with the 

 superior labials; the frontal is much smaller than the anterior frontal ; it has 

 immediately behind it the inter-parietal, and upon the external aspect of its pos- 

 terior border the parietal ; the inti^r-parietal is a small plate resembling the frontal 

 in form, but smaller; the parietals are more extended in the transverse direction 

 than longitudinally ; in front they touch the ocular and supraocular, latero-exter- 

 nally the frontal, and posteriorly the inter-parietal; four small quadrangular plates 

 margin the upper lip on each side; the eyes are latero-superior placed as above 

 mentioned ; the body is slender, of nearly uniform size, somewhat thicker near the 

 middle, covered with scales which are broader than they are long, presenting a 

 rounded margin posteriorly, somewhat smaller near the head than upon other 

 parts of the body ; of these scales there are 29 longitudinal, and 344 transverse 

 rows; there are 16 rows upon the tail ; the tail terminates in a pointed spine. 



Coloration. — (From a specimen in spirits.) The entire under surface of the 

 animal is yellow, without spots ; the back presents iO narrow black lines, ex- 

 tending from the head to the extremity of the tail ; of these the two exterior are 

 less distinct than the rest; the three central ones become broader toward the tail; 

 the intervening portion i.s white or silvery grey. 



Dinteasio/is. — Length of head 2 lines; greatest breadth transversely 2i lines; 

 length of tail 2 lines; length of body 8 inches 2 lines, (I'r.) greatest circum- 

 ference 7 lines. 



llubllat. — Liberia, West Coast of Africa. Specimen in the Museum of the 

 Academy. 



General Observations. — The reptiles above described, belong to the first section 

 of the Ophidians, described by Uumeril and Bibron; viz., the Scolecophidians,* 

 or vermiform non venomous serpents. There can be no doubt, we think, 

 that they are new. But three species of the genus Onychocephalus are described 

 hy them in their Erpetoiogie generale, or Histoire Naturelle complete des reptiles, 

 which con tains descriptions of all the species of reptiles known. They are the Ony- 

 chocephalus Delaiandii, multilineatus, and unilineafus The first is figured in the 

 work of Dr. .'\ndrew Smith, upon the Zoology of Southern Africa, and does not 

 bear the least resemblance to either of them, differing from both in size and in the 

 relative proportions of the head and tail, and in its coloration, being of an uniform 

 brown colour, both upon its upper and under surface In multilineatus the tail is 

 double in length the breadth of the head, and the body presents a series of white 

 lines upon a ground of silvery grey. In unilineatus a single black line passes 

 along the median line of the back, which is of an olive-brown colour. 



* P'rom SxwTujjj fxdj, vermis, lumbricus, et o^i^, serpens. 



