204 BULLETIN 15 4, UNITED STATES NATIONAL MUSEUM 



Even the youngest specimens show stripes of uneven Avidth. The 

 lateral fiekls bear spots in the young which enhirge and unite with 

 the stripes to form crossbars, but a secondary encroachment of the 

 dark ground color of the fields tends to suppress these bars and to 

 maintain only a longitudinal arrangement of the dorsal markings. 

 Thus, the area where the spot was originally may be secondarily 

 covered by black, the white color having migrated to the stripes. 

 The centers of enlargement in the stripes of aged individuals are 

 formed by either embryonic or juvenile evolution of the color pattern 

 in this manner. In ruMdits, the cross-bars become dominant at the 

 expense of the dark coloration so that a confluent longitudinal 

 arrangement of the dark fields is not maintained in the adult. 



Only nine specimens of celeripes, including the type, have been 

 available for this study. The data obtained may be summarized as 

 follows: Body, G8-116 mm.; tail, 210-30G; total length, 278-411; 

 length of tail as percentage of total length, 71.5-75.4; width of head, 

 10-20; width of head as percentage of body length, 13.7-17.2; hind 

 leg, 50-7G; length of hind leg as percentage of body length, Gl.0-74.5; 

 supraocular granules extending forward to the middle of the third 

 supraocular in two specimens, to the posterior border of the second 

 supraocular in four specimens, and to the middle of the second 

 supraocular in three specimens. 



Range. — This form is known only from San Jose Island in the 

 Gulf of California. Dickerson (1919) in the original description 

 stated that " The range probably includes the mainland of Lower 

 California from the Gulf northward from La Paz and San Jose; 

 Island. * * * j^ jg pi'obably the species from Santa Kosalia 

 and Mulege, identified by Mocquard (1899) as Cnemidophorus gni- 

 haviii Baird and Girard. " Since all of the mainland members of 

 the tessellatus group that the writer has examined from this gen- 

 eral region are typical riibidus, it seems that Dickerson's assumptions 

 were largeW theoretical. The nearest approach to the type of dor- 

 sal coloration found in celeriqyes' is presented by certain specimens 

 of tessellatus from distant regions. These latter have the general 

 dorsal pattern of celcripcs, but they do not have a red or pinkish 

 coloration ventrall3^ Specimens taken hetween San Jose and San 

 Marcos islands, consisting of both mainland and insular represen- 

 tatives, have proved to be Qnihidus, and not celervpes., or tessellatus, 

 and intergrades between tnihidus and tessellatus have been found on 

 San Marcos Island. This seems to exclude the possibility of celeri- 

 ■pes being directly derived from tessellatus or of the more northern 

 Santa Rosalia specimens being celeripcs or ruhidus. The Santa Ro- 

 salia specimens are therefore referred to tessellatus. Since the Mu- 

 lege examples are in the probable range of rvhidus they are referred 



