1903.] NATURAL SCIENCES OF PHILADELPHIA. 547 



mour, Baylor county, in northern-central Texas, have similarly coarse 

 scales, one has the collar-edge occupied by a row of granules, and in 

 another the large scales of the collar are most distinct in the centre. 

 The pale dorsal area shows a tendency to contract and take on the 

 form of a median stripe. All these differences being in the direction 

 of C. perplexus. These specimens are noticeable for their small num- 

 ber of femoral pores, which are in each 13-14; (2) 14-15; 15-16. The 

 usual range in sexlineatus being 15-19. 



Cnemidophorus sexlineatus perplexus B. & G. 



I have a number of specimens from Pecos. Compared with sex- 

 lineatus most of them have a slightly longer snout, causing the loreal 

 and sometimes the postnasal to be elongated. There are seven light 

 stripes, the additional one being median and of the same width as the 

 laterals. This replaces the light dorsal area of sexlineatus. Usually 

 the light stripe on the back of the thigh is absent, but it is well marked 

 in one young example 110 mm. long. The collar scales are less en- 

 larged and occupy a somewhat triangular space in the centre, and the 

 edge of the collar is usually formed by one or two rows of small granules, 

 although two of my specimens have large scales on the edge. The 

 gular tract of minute scales contrasts less strongly with those surround- 

 ing it, and the dorsal scales are coarser. According to Cope the femoral 

 pores are 19, but in ten which I have examined they are 13-18, averag- 

 ing 15. The hind leg may reach the axilla or the eye, but in most cases 

 about touches the ear. One of my specimens has the anterior supra- 

 orbital separated from the next one by small granules. The largest 

 is 222 mm. long (tail 158). The proportions are slender. 



Prof. Cope regards this form as a subspecies of tessellatus, with which 

 in general its scutellation agrees, though I find the number of femoral 

 pores to be much less; but it does not appear to take on the spotted 

 pattern of that species, and the fact that both sexlineatus and perplexus 

 are striped at all ages and are more nearly equal in size and proportions, 

 in connection with their disposition to intergrade where they come 

 together in Texas, seems to indicate that they should be placed to- 

 gether as subspecies. In both of them a few of the postantebrachials 

 are sometimes a little enlarged, but in no case that I have seen do they 

 even approach the large scuta characteristic of C. gularis. 



Cnemidophorus grahami B. & G. 



This species is almost identical with C. s. sexlineatus in scale charac- 

 ters. The one specimen in the present collection has 21 femoral pores, 

 which agrees with the number given by Cope. It has a freno-orbital 



