154 DK. R. W. SHUFELDT ON [Apr. 1, 



are found to be largest on top of the head, more especially on the 

 lateral parietal regions, and over the entire facio-frontal aspect ; here, 

 as in the case of the smaller mesial ones, they are crowded close to- 

 gether, are of varying outline, but in no specimen are they arranged 

 upon any definite plan as they are in some other Lizards, in Lacerta 

 for example, iloreover, they do not quite agree in any two specimens, 

 a fact that, upon comparison, at once becomes evident. Tubercles of 

 a similar character extend down upon either side of the head as far 

 as the commissure of the gape, filling in the region between the eye 

 and the aural entrance : these gradually become smaller as they near 

 the throat, which latter space is entirely covered over by an even 

 layer of closely-set tubercles of a very much smaller size and of a 

 uniformly subcircular form. Here these peculiar scales are the 

 smallest of the kind as compared with those anywhere else on 

 the body of this reptile : they are all in contact with each other, 

 unless the animal from some cause swells out its throat, when the 

 skin may be seen in the evenly distributed interspaces. Upon 

 studying the arrangement, number, and distribution of the circum- 

 ocular, narial, and labial scales in these two specimens of mine, 

 I find that in none of these particulars are they exactly alike. A large 

 oblong rostral scute is present, with a smaller scute upon either 

 side of it, while external to either of these is a quadrilateral sub- 

 narial scute. Next follow the superior labials proper, the marginal 

 ones being usually nine in number on either side, which become 

 gradually smaller as we proceed from before backwards. Above the 

 anterior moiety of these labials, extending between eye and nostril, 

 there is another row of smaller size, some fire or six in number, 

 which I am of the opinion will be pretty constantly found in that 

 locality. Of tiiis latter row the largest scute is just posterior to the 

 nostril, while the smallest and most posterior one, triangular in form, 

 is wedged in just beneath the suborbital row. Three large tubercles is 

 the rule for the supraciliary scutes, with four suborbitals, and either 

 one or two small post- and preorbitals. Normally, again, there seem 

 to be two anterior nasal scutes, with a large postnasal one, and 

 commonly one wedged in above and between these two. Passing 

 next to the arrangement of these upon the mandible, we find 

 always present a fair-sized chin-scute, followed posteriorly by four 

 mental scutes, on either side of the median line, while the lower 

 labials seem to average fourteen in number. Between these latter 

 and the mental scutes, the interval is filled in by three oblique rows 

 of flat scutes, those of the larger size being in the most external row, 

 while the smallest occupy the inner one, and these latter gradually 

 merge into the area of small tubercles which overlay the throat and 

 which have been already described above. 



We may now turn our attention to the scutation of this reptile's 

 body, and we find upon the dorsal aspect that the tubercles 

 gradually diminish in. size as we pass backwards from the occipital 

 region, although they maintain very much the same character and 

 arrangement. Soon, however, they commence to dispose themselves 

 in regular transverse rows and are of a pretty uniform size. This 



