1931 ] 
Structure of Notiothauma reedi 
9 
different figures) is the coxite, and the distal portion ( st 
in the different figures) represents the entire stylus, so 
that I have provisionally adopted this view of the interpre- 
tation of the parts of the gonopods in the present paper. 
Mr. Snodgrass is inclined to regard the basal collar called 
the “cardo” in the genitalia of Hymenoptera, as a detached 
basal portion of the coxites, which has united with its fel- 
low from the opposite side to form a basal collar-like sclerite 
in these insects, while the basal segment of the (outer) 
claspers represents the remainder of the coxite, and the 
outer claspers themselves represent the styli, in the 
Hymenoptera, and this view seems to be as reasonable as 
any, since it is in accord with the evidence of the muscula- 
ture of the structures in question. It should not be for- 
gotten, however, that Emery, Wheeler, and other students 
of the ants, interpret the basal and distal portions of the 
outer claspers (i. e., the gonopods) as parameres, and the 
question of the homologies of the parts of the gonopods is 
by no means settled as yet. In the following discussion, I 
shall refer to the claspers st of figs. 3, 7, 8, etc., as the 
gonostyles, and shall designate the basal portions cx as the 
gonocoxites, terming them both together, the gonopods. 
The gonopods st and cx of Notiothauma (figs. 1, 5 and 7) 
not only furnish the prototypes from which the gonopods 
of the Panorpidse and other Mecoptera could be derived, 
but they are also surprisingly like the gonopods of primi- 
tive Diptera such as Trichocera (fig. 3), suggesting that the 
ancestors of the Diptera were very like Notiothauma in the 
character of their genitalia. Thus, the gonostyle st of 
Trichocera bituberculata Alex., shown in fig. 3, has a medio- 
tubercle m and a basitubercle b astonishingly like the medi- 
tubercle m and the bastitubercle b of the gonostyle of Notio- 
thauma shown in fig. 7, but I have not found any Dipteron 
in which the gonostyle (st of fig. 3) bears a peculiar 
stylorganus^ (or stylar organ) like that labelled o in the 
gonostyle st of Notiothauma shown in fig. 7, although such 
a stylar organ is not found in all of the Mecoptera either, 
being apparently absent in Chorista and' Panorpodes (figs. 
12 and 13) and in all of the Panorpidse and Bittacidse that 
I have examined. A stylorgan o is present in Notiothauma 
