290 



DR. H. GADOW ON EVOLUTION 



[Mar. 20, 



in the IS'orth-west, whence it has sent a few outlying forms east- 

 wards through the basin of the Rio Gi'ande. The GULARis-gronp 

 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-ioYiws, near Monterey) the only species known in 

 Nuevo Leon and Tamaulipas. C. communis extends from Jalisco 



Text-fig. 66.* 



12 3 3 2 1 



3 3 



V 



3 3 



^ A- -45 4- -+54 4- 55 4 



^ F- G H ^1 



Evolution of Pattern of C deppei, from 6 to 11 pde stripes. 



* In all these diagrams of pattern evolution the Arabic refer to the tvhite 

 stripes or their subsequent changes. The Soman numerals refer to the Fields. 

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

 passes through the Mar, along the flank and upon the Thigh. Stripe 2 passes 

 through the JEi/e, above the Hip and upon the Tail. Stripe 3 encloses the mid-field 

 when there is no fourth pair of stripes. 



