706 THE AMERICAN NATURALIST. 
mouth parts, of whose homologies no doubt can exist, and the 
forming imaginal parts, of whose homologies, in definitive con- 
dition, I thought myself long ago able to speak confidently on 
a basis of comparative anatomical study, but of which now on 
a basis of ontogenetic study I am simply without doubt. 
STANFORD UNIVERSITY, CALIFORNIA. 
January, 1902 
