98 
Psyche 
[March 
The Bittacidse (superfamily Bittacoidea) are quite dif- 
ferent from the rest of the Mecoptera in the character of 
the terminal abdominal structures of the male and female, 
and their slender bodies are modified along- lines leading 
away from the typical scorpionfly trends. I, therefore, 
have no hesitancy in placing them in a distinct suborder, 
the Metamecoptera. The origin of these insects is obscure, 
although there is some evidence that they might have 
descended from the same ancestors from which the fossil 
Neorthophlebiidse, were derived. It is more probable, 
however, that the Bittacidse were derived from ances- 
tors resembling those of the Panorpidse. In the character 
of the male genitalia, the Choristidae suggest the origin of 
the peculiar type occurring in the Bittacasidse, and this 
might be taken to indicate a common ancestry for the Chor- 
istidae and Bittacasidse. The terminal structures of the 
female, however, would not bear this out, and until more 
is known of the comparative anatomy of the Mecoptera, it 
will be impossible to determine what family is the most 
closely related to the Bittacidse, which occupy a rather iso- 
lated position in the order Mecoptera. 
The terminal abdominal structure of the female Mecop- 
tera have been figured in the December, 1928, issue of the 
Journal of the N. Y. Entomological Society, and the features 
referred to above are showm in this paper. The genitalia of 
the males of the Mecoptera referred to above are shown in a 
paper published in the Trans, of the American Ent. Society, 
1928, 48, p. 207. The terminal structures of related Mecop- 
tera will be discussed in the paper dealing with the male of 
Notiothauma, in which the anatomical features of the allo- 
type will be shown in detail. 
Abbreviations 
A. Anal veins. 
a. Jugalula or “alula, ” containing the axillary veins, 
af. Alafimbrium or alular fringe. 
b. Bullae or “pellucidae.” 
ba. Basarcus, or basal arch of the first anal vein. 
be. Basicosta. 
bcs. Basicostal bristle.s 
