No. 380.] THE WINGS OF INSECTS. 563 
the homology of the elytra. We are forced to conclude that in 
this order the wings are so modified that the typical branching 
of the veins is lost. We have examined, however, a compara- 
tively small series of coleopterous pupz; and it is quite possible 
that generalized forms may yet be found in which the typical 
branching of the veins is preserved. 
We refer to the veins instead of to the trachez in this con- 
nection, as some observations that we have made indicate that 
in the Coleoptera as in the Hymenoptera the venation of the 
Fic. 51. — The tracheation of the wings of a cerambycid pupa. 
wings precede their tracheation, and that the courses of the 
main trachez are determined by the courses of the preéxisting 
veins. 
Returning to the question of the homology of the elytra, the 
most conclusive evidence that we have found is the fact that a 
very close correspondence exists between the tracheation of the 
elytra and that of the hind wings. And what is especially 
striking is that similar modifications occur in the two pairs of 
organs, 
The accompanying figures of the elytra and wings of two 
cerambycid pupz illustrate this point. And the lettering of 
