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REPORT OF THE STATE ENTOMOLOGIST 1907 235 
many aberrancies; and there is one here in the little group of genera 
of more typical Eriopterini shown on plate 23. The upcreep of the 
tips of the two veins under discussion toward the apex of the wing 
has already been noted in an earlier place for its effect upon the 
development of the cell 1st M2. It is also noteworthy for having 
‘relieved the deflected base of M,,, of its ordinary responsibility. 
That deflected portion in Mesocyphona tends to atrophy, and thereby 
to reduce the rearward extension of the cord. 
In like manner vein M? is deflected upward just beyond its 
union with Cu! and thereafter it tends to atrophy as in Dicranomyia, 
‘or to be reattached to vein M** in the manner already discussed, 
and more fully illustrated in the accompanying diagram [ fig. 16]. 
If any one would comprehend what has happened to the 
median vein in the Tipulidae, let him study the wings of the 
plates carefully in comparison with this diagram. a is the hy- 
Fig. 16 
pothetical typical media, with the dotted lines in this and in 
all the following indicating the positions of the cross veins. 
b, c, d and e represent the Ptychopterid line of specialization. 
b is Macrochile, with the media reduced to three branches; c 
is a hypothe? al form introduced to account for the disappear- 
ance of the posterior division of the first median fork’. 
Material is lacking to fill this gap, and another interpreta-. 
tion is possible: i.e. that, starting with a form somewhat like 
Megistocera |pl. 16, fig. 4] the median cross vein has been lost 
and the branches have regularly and progressively fused to- 
gether, M! and M? completely, leaving these same two tips in 
Ptychoptera to be designated as M1 and M?. But the first 
interpretation is certainly admissible, from the frequent tend- 
ene ynOle Vea aida Viemtomatropliys and it ase rendered much the 
*This makes two tips of media remaining in Ptychoptera M* and M?. 
