238 NEW YORK STATE MUSEUM 
opposed to this interpretation or favoring any other. It seems 
clear that vein M! occupies the more advantageous position; the 
hinder branches lie in the field in which reduction proceeds fastest, 
and the stages of their disappearance are easily traced, as has been 
illustrated for the Tipulidae in the foregoing pages. Undoubtedly, 
in this family at least, M* is the most persistent of the branches of 
anecia, Oyn joeiee 1G Ine Saws, ~ Ik tae town wera [WL] is whee 
branched and the discal cell [cell 1st M?] present, the vein 
separating the discal from the second basal [cell M]| is of course 
the first section of the proximal | posterior | branch of the fourth 
vein [M,]; if the fifth vein [Cu] is really the one that is three 
branched, then this vein, at the outer end of the second 
basal [cell MJ], is always a true cross vein, which it always ts 
m the Comstock system when the discal cell 1s absent.’ The part 
of this statement italicized above is a complete and incomprehensible 
misstatement. Vein M#? in the Comstock system.is always M%, 
never anything else, whether the cell 1st M, be closed or open. 
Moreover, cell 1st M? is merely the space in the basal part of the 
first fork of the median vein, whether it be delimited externally 
by a median cross vein or not. It does not depart for other 
fields when specializations occur about it, but stays in that 
fork. This is the difference between the Comstock system and 
the others — it has a morphological basis. It recognizes a difference 
between principal veins and branches of the same. It does not 
begin in the middle of the wing to enumerate veins after a few have 
been dismissed under a different sort of designation. It does not 
take as its standard of comparison the most specialized of wings 
with reduced venation. It deals primarily with the real structural 
entities of the wings, the veins and cross veins, and not with the 
spaces that these leave vacant. 
And the “ great cross vein”’ of Osten Sacken (the basal deflection 
of Cu’) will not be greatly helped by calling it some other kind of 
a cross vein, since it 1s not a cross vein at all. But neither the 
Loewian code of medieval terminology, nor the Schinerian version 
of it—-neither as corrupted by Osten Sacken nor as purified by 
Williston — with its peregrinating posterior cells, its discal cell 
emitting veins to the hind margin, its cross veins great and small 
and misconceived, and its wearisome confusion of the simplest 
elements of the venation, needs that it should be criticized. What 
these are and whence they came and why they work as they do are 
self-evident. It were better to say of them that they have served 
their day and generation. 3 
