86 
Psyche 
[June-Sept. 
the nature of the parameres of male Coleoptera and Hy- 
menoptera, which represent the starting point for the deriva- 
tion of the genital forceps of male Meeoptera, Trichoptera, 
Diptera, etc. Since the Coleoptera are more “orthopteroid” 
than the Hymenoptera, the condition exhibited by their 
genital structures should be more primitive, or ancestral, 
than is the case with the parts in the Hymenoptera, and the 
Hymenopterous type was probably derived from the more 
primitive Coleopterous type of genitalia occurring in such 
primitive Coleoptera as the Lampyridse. In males of the 
common Lampyrid beetle Lucidota corrusca, the unseg- 
mented parameres are borne on a broad basal ring corre- 
sponding to the narrower basal ring labelled gc in Fig. 11 
of the primitive Hymenopteron Xyela (so that this type of 
basal ring is not peculiar to the Hymenoptera alone, as is 
commonly thought to be the case) in which the basal ring 
bears a pair of segmented forceps occupying exactly the 
same position (on each side of the median aedeagus) that 
the unsegmented parameres do in Lucidota. It is therefore 
evident that the unsegmented parameres of the more primi- 
tive Coleoptera merely become secondarily divided into a 
basal and distal segment in the Hymenoptera, although 
Snodgrass, 1941 (Smithsonian Misc. Collections, Vol. 99, 
No. 14) considers that the parameres of the Hymenoptera 
are represented by only the distal segments of the forceps. 
In the following discussion the basal segment of the forceps 
will be referred to as the basimere or basistyle (b of Figs. 
11 to 13) and the distal segment of the forceps will be termed 
the distimere or dististyle (d of Figs. 11 to 13) . 
In the Bulletin of the Brooklyn Entomological Society for 
1938, Vol. 33, page 3, the writer first called attention to the 
fact that in male Meeoptera Diptera, etc., the basimeres 
(b of Figs. 12 and 13) do not represent abdominal coxites, 
and the distimeres (d of Figs. 12 and 13) do not represent 
styli, as is commonly supposed to be the case, but these seg- 
ments of the genital forceps of the Meeoptera, Trichoptera, 
Diptera, etc., are clearly homologous with the segments 
labelled b and d of the parameres of such a Hymenopteron 
as that shown in Fig. 11 ; and it is difficult to understand 
how anyone could examine such a series of genital forceps as 
that shown in Figs. 11, 12 and 13, without immediately 
