290 



DR. H, GADOW OX EVOLUTION 



[Mar. 20, 



in the Nortli-west, whence it has sent a few outlying forms east- 

 wards througli the basin of the Rio Grande. The GiLAias-gvoup 

 is strong along the Western Sierra. C. gularis itself is the only 

 kind which follows the same basin, and it is (with the exception 

 of some tessellatus -iovn\» near Monterey) the only species known in 

 Nuevo Leon and Tamaulipas. C, communis extends from Jalisco 



Text-fiff. G6.* 



12 3 3 2 1 



3 3 



H 



7b Thiqh 



■4. 4- -45 4 •* 5 4 



3 3 



E F G H 



Evolution of Pattern of C. deppei, from G to 11 jiale stripes. 



* In all these diagrams of pattern evolution the Arahic refer to the white 

 stripes or their sulseqnent changes. The lionnni iiumerals refer to the Fields. 

 Field I lies betiveen stripes 1 and 2, Field II between stripes 2 and 3. — Stripe 1 

 passes through the Far, along the flanh and upon the Thigh. Stripe 2 passes 

 through the Fye, above the Hip and upon the Tail. Stripe 3 encloses the mid-field 

 when there is no fourth pair cf stripes. 



