NATURAL SCIENCES OF PHILADELPHIA. 329 



gentilis, but the head and eye larger. Color above brownish red, with 

 thirty-one pairs of narrow black half-rings enclosing white spaces, from head 

 to anus. The black rings not extending across the abdomen, which is uni- 

 form yellowish white. Head black above. 



Descr. Snout broader and more depressed than in L. g e n t i 1 i s . It 3s 

 also more elongate, and hence, also, the loreal and nasal plates ; in the only 

 specimen examined the second superior labial plate is replaced by two smaller 

 ones, thus increasing the number to eight, a peculiarity probably abnormal, 

 as all the other species of the genus have seven. The body above is brownish 

 red in spirits, crossed by thirty-one pairs of black rings from head to anus. 

 The enclosed white spaces are one and a half scales wide on the central fifteen 

 dorsal rows, and begin to widen abruptly on the fourth lateral row on each 

 side, extending over three or four scales longitudinally on the first row. On 

 the sides they are punctulated with black as in L. g e n t i 1 i s . The occipital 

 white ring is much broader. The black rings are each two scales wide on the 

 vertebral region, narrowing to less than one scale laterally. On the fourth 

 lateral row the two rings of each pair begin to diverge, the anterior uniting 

 on the edge of the abdomen with the posterior ring of the pair in advance, the 

 posterior becoming confluent with the anterior of the succeeding pair. Thus 

 the ground color is enclosed in the form of a transverse elliptical spot. Upon 

 the middle of the body these spots are two or three scales wide on the verte- 

 bral region, four or five on the sides, and but one on the first row of scales. 

 Anteriorly the red intervals are greater ; posteriorly they narrow slightly, but 

 toward the tip of the tail they are entirely lost, as in L. doliatus and 

 gentilis, by the confluence of the black rings. The black rings extend 

 but a short distance upon the abdominal scuta, leaving the abdomen destitute 

 of blotches, though it is faintly and sparsely punctulated. The chin and in- 

 ferior labials are tinged with brown. The top of the head is black as in L. 

 gentilis. 



No. 1842, Fort Lookout, Nebraska. Lieut. Warren and Dr. Hayden. 



The number of rows of scales and the more numerous rings will distinguish 

 this species from L. annulatus, and those above compared with it. 



L. annulata Kennicott. 



Spec. char. Form stout, head broad, eye small. Scales short and broad. 

 Color bright red, with eighteen to twenty-two pairs of black rings from head 

 to anus, each pair enclosing an immaculate yellow ring which completely en- 

 circles the body, widening but little upon the flanks. Abdomen between the 

 yellow rings black. Top of head entirely black, this color extending posteri- 

 orly upon the occipitals in an acute angle. A broad occipital yellow ring. 



Descr. General appearance similar to L. gentilis. The form is stouter, 

 the head shorter, broader and more depressed, and the eye smaller. The 

 dorsal scales are very different, being much broader; the lateral rows in L. 

 annulatus, are higher than long, and those of the central are nearly as 

 wide as long. InL. gentilis, those of the lateral rows are considerably 

 longer than high, and those of the central nearly twice as long as wide. There 

 are twenty pairs of black rings from head to vent, which do not diverge on 

 the sides ; each ring covering two to two and a half scales longitudinally on 

 the vertebral region and narrowing but little laterally. The enclosed yellow 

 rings are one and a half scales wide on the vertebral region. The first three pairs 

 of black rings behind the head are, with those enclosed, a little wider. The 

 intervals of red ground-color occupy four or five scales on the middle of the 

 body, and one or two more anteriorly and posteriorly. The yellow rings are 

 of nearly uniform width, and completely surround the body. The spaces be- 

 tween them on the abdomen are black. There are no black spots upon the 

 body. 



Type No. 4293. Matamoras, Mexico. Lieut. Couch. 



425, Mexico. Paris Museum. 



I860.] 



