70 BULLETIN 15 4, UNITED STATES NATIONAL MUSEUM 



with white. The unicolor phase probably does not occur in depim. 



Anal spurs, althougli often found in lemniscatus, are universally 

 absent in guttatus. 



Description. — Snout moderately elongate ; nostril anterior to nasal 

 suture; anterior nasal usually not in contact with second upper 

 labial; supraoculars normally 3; supraocular granules usually small, 

 forward extent variable; frontoparietals normally 2; parietals 3; 

 anterior gulars moderate to large, graded, largest centrally; posterior 

 gulars smaller, contrasted with anterior gulars; mesoptychial scales 

 moderate to large, largest centrally or medio-laterally, graded and 

 smaller laterally, in 2-5 rows; postmesoptychial granules minute, 

 sometimes extending to edge of posterior gular fold. 



Body elongate; ventral plates in 8 longitudinal and 30—10 trans- 

 verse roAvs; dorsal granules minute to moderate; limbs well de- 

 veloped, strong; brachials 4—7; antebrachials 2-3; brachials and ante- 

 brachials continuous or subcontinuous at a point of contact; post- 

 aiitebrachium covered with small or slightly enlarged granules; 

 f emorales 5-10 ; tibials 2-4 ; femoral pores 17-26 ; tail elongate, taper- 

 ing ; subcaudals smooth ; lateral and dorsal caudals smootli or weakly 

 keeled, slightly oblique, and moderate in size, keels irregularly 

 arranged. 



Coloration variable; lower surfaces white to dark blue, often slaty 

 or slaty blue, especially in the young; lower surface of tail usually 

 white or yellowish, upper surface brown, blue, or olivaceous usually 

 not spotted or reticulated; tail with a narrow, diminishing, lateral 

 stripe on each side anteriorly, seldom with two stripes on each side; 

 femora weakly spotted or reticulated with white; l)ack unicolor, 

 spotted or lined; if unicolor, traces of stripes may be present later- 

 ally; if spotted, lines may or nuiy not be present laterally; if lined, 

 spots may or may not be present dorsally or posteriorly, stripes 

 varying from six to eight in normal individuals, width of stripes 

 variable; dorsal ground color usually blackish or gray, seldom 

 brownish. 



A series of 448 specimens of the INIexican race runner has been 

 examined, and data from 300 of these may be presented as follows: 

 Body, 35-138 mm.: tail, 130-295; total lengtli. 184-425: length of 

 tail as percentage of total length, 60-73.2; width of head, 6-22; 

 width of head as percentage of body length, 12.0-15.7; hind leg, 

 26-83; length of hind leg as percentage of body length, 58.0-77.4; 

 frontoparietals partly united into a single scute in 3 specimens, dis- 

 tinct and in two scutes in 292 specimens, and abnormally split into 

 three scutes in 5 specimens; supraoculars three in 279 specimens, 3-4 

 in 10 specimens, and 4 in 11 specimens ; supraocular granules extend- 

 ing forward to the middle of the third supraocular in 113 specimens, 

 to the anterior border of the third supraocular in 78 specimens, to 



