92 Annals Entomological Society of America  [Vol. XIV, 
since the tendencies present in such Neuroptera as Nemoptera (e. g., 
the reduction of the hind wings to mere ribbon-like structures, suggesting 
the precursors of the halteres of Diptera, the elongation of the head 
region and the slender character of the mouthparts, which apparently 
presage similar tendencies occurring in the Diptera, the nature of the 
male genitalia, etc., which are somewhat like those of certain Diptera) 
are those which one finds recurring in many Diptera, and a number of 
these tendencies are also exhibited by certain Mecoptera. In fact, 
Nemo ptera has more features suggestive of affinities with the Mecoptera 
and the Diptera than any other Neuropteron which I have been able 
to examine, and it serves as a connecting-link between the Neuroptera 
on the one side, and the Mecoptera, with the Diptera, on the other. 
Nemopiera, however, is a rather highly specialized Neuropteron, and, 
since the Mecoptera (and even the Diptera also) have retained certain 
features (genitalia, etc.) in a more primitive condition than Nemoptera 
has, the probabilities are that the Mecoptera (and Diptera) were 
derived from a common ancestral type which gave rise both to 
Nemoptera and to the Mecoptera, etc. Aside from the presence of the 
ligula, ‘“‘lg,’’ in Nemoptera (Fig. 86) the mouthparts of this insect are 
apparently even more like the mouthparts of the Mecopteron Bzttacus 
(Fig. 85) than they are like the mouthparts of other Neuroptera, as one 
can see by comparing Fig. 86 of Nemoptera with Fig. 81 of a Neuropteron 
fairly closely related to Nemoptera, since the slender columnar structure 
bearing the labels ‘‘sm’’ and ‘“‘mn”’ in Fig. 86 of Nemoptera bears a 
much stronger resemblance to the region bearing these labels in Fig. 85 
of the Mecopteron Bittacus, than it does to the region bearing these 
labels in the Neuropteron shown in Fig. 81. Similarly the long slender 
maxillary galea, ‘‘ga,’’ and the slender lacinia, “‘la,’”’ with its peculiar 
fringe in Nemoptera (Fig. 86) resemble the structures bearing the same 
labels in Bittacus (Fig. 85) much more closely than they do the structures 
bearing the same labels in the Neuropteron shown in Fig. 81. These 
and many other features of the body in general indicate a close relation- 
ship between Nemoptera and the Mecoptera (with the Diptera), and I 
am convinced that the immediate ancestors of the family to which 
Nemoptera belongs (i. e., the Nemopteridz) bore a very striking resem- 
blance to the ancestors of the Mecoptera (with the Diptera). At any 
rate, we must admit that in order to properly interpret the homologies 
of the mouthparts, etc., of the Mecoptera and related forms, it is 
necessary to first study these structures in Nemoptera, so that there can 
be no. possible objection to regarding Nemoptera as a form 
morphologically annectant between the rest of the Neuroptera and 
the Mecoptera (with their allies) even though Nemoptera itself may not 
stand in the direct line of descent of the Mecoptera and Diptera. 
The Hymenoptera exhibit some very close resemblances to the 
Neuroptera in the nature of the mouthparts, and I am rather surprised 
that the points of similarity between the Coleoptera and Hymenoptera 
found in other structures, are not more evident in the mouthparts, 
although when more favorable material has been studied, other forms 
will doubtless be found which exhibit a greater resemblance between 
