316 



The Mechanism of Evolution in Leptinotaesa 



55 41 



818 Males. Total 1546. 

 Fio. 132. — First census at San Marcos In 1908, showing the pronotal pattern. 



41 1 



^^f^^^M — ^^^ 



38 56 41 



728 Females. 



•55- H 



47 



85 



90 



■-29 



214 



19 



46--^ 



1073 Males. Total 2263. 1190 Females. 



Fio. 133. — Second census at San Marcos in 1908. showing sudden change In 

 the population as a whole and sudden appearance of isolated groups In biotypes 

 6, 8, 12, and 10. 



^^1— 87- 



11 — f^\ 



41 '-^J^ 



II 



/ / 



51 12 



"mm 



---17 



V \ V 



9 31 55 



1230 Males. 



61 ^Csm. 



60 -^mm). ,^f— 141 



\— 96 



44--^---3P^^^--109 



86 





26 25 31 11 41 33 



Total 2531. 1301 Females. 



Fig. 134. — First census at San Marcos in 1909, showing an increased array 

 In pattern conditions with total elimination of isolated groups present in the popu- 

 lation in previous censuses. 



