206 BULLETIN" 15 4, UNITED STATES NATIONAL MUSEUM 



the sides, although the reticuhitioiis soiiietinics tend to break into 

 spots to produce a pattern simihir to that found in the closely related 

 southern forms, hacatus and catallnensis. 



Martyrls is very close to caniis, differini^ from it merely in the 

 possession of a much darker ground color. The lower labials of all 

 of the martyrls specimens examined are deep brown or black, while 

 those of typical canus are colored some shade of light gray, slate oi 

 broAvn. On South San Lorenzo Island there are such perfect inter- 

 mediates between the two forms that they can not be conscientiously 

 referred to either subspecies. These are discussed in detail under 

 canus. 



The whiptail of San Pedro Martir Island ditfers from typical 

 tesseUatus in its much smaller maximum size, in a relative reduction 

 of the length of the hind limbs, and in the obsolescence or extreme 

 fineness of the dorsal and lateral reticulations. However, it is very 

 closely approached by certain specimens of this form. 



Descriptio7i. — Snout moderately blunt; nostril anterior to nasal 

 suture; anterior nasal not in contact with second upper labial; supra- 

 oculars normally 4 ; supraocular granules not extending forward past 

 the anterior border of the third supraocular; frontoparietals 2; 

 parietals 3; occipitals small, largest anteriorly; anterior gulars mod- 

 orate, often enlarged centrally; posterior gulars smaller, uniform; 

 mesoptychial scales rather small, in 5-T transverse rows, median 

 scutes in each row a little larger. 



Body moderately elongate; ventral plates in 8 longitudinal and 

 35-39 transverse row^s; dorsal granules small; limbs rather Aveak, 

 somcAvhat shortened ; brachials 4-6 ; antebrachials 3-4 ; brachials and 

 antebrachials more or less continuous at a point of contact ; postante- 

 brachials usually not enlarged, often finely granular; femorals 5-8; 

 tibials 3-4; femoral pores 16-20; tail elongate, tapering; caudal 

 plates large, oblique, with rather strong lateral longitudinal keels. 



Coloration distinctive; under surfaces usually suffused with much 

 blackish or shiny black ; gular region very dark, black or smoky ; 

 all caudal surfaces chocolate to black, usually darker below; back 

 and femora unicolor or covered with many fine white spots and re- 

 ticulations, these often shoAving a definite transverse arrangement 

 or tiger-barring; usually no indication of longitudinal arrange- 

 ment in the dorsal markings; dorsal ground color blackish, this 

 often appears as a continuous suffusion from the deep blackish 

 A^entral surface below. 



A series of 12 specimens of 'nmHyrls (C.A.S. Nos. 50565-50576) 

 exhibits little variation in the dorsal coloration. The dorsal mark- 

 ings in certain specimens (50565, etc.) are coarse and more distinct 

 than they are in certain other specimens (50570-50572). If these 

 animals are but casually observed, there is no indication of a longi- 



