ArT, 4. REVISION OF THE FAMILY THEREVIDAE—COLE. 7 
In all the species the proctiger is a separate plate, considered an 
eleventh segment by some morphologists, and has two narrow flaps 
above; these flaps are in some cases quite conspicuous. There is 
some variation in the form of the aedeagus and good specific char- 
A 
Fic. 2.—M ALE GENITALIA. A. DORSAL VIEW OF APEX OF ABDOMEN OF PSILOCEPHALA FRONTALIS. 
B. INTERNAL GENITAL ORGANS OF SAME, C. NINTH STERNITE OF P. FRONTIILIS. D. INTERNAL 
GENITAL ORGANS OF PSILOCEPHALA HAEMORRHOIDALIS. FE, NINTH STERNITE OF P. HAEMOR- 
RHOIDALIS. 
Fig. 3.—MALE GENITALIA. A. APICAL SEGMENTS OF DIALINEURA CRASSICORNIS. B. VENTRAL VIEW 
OF SAME. C. INTERNAL GENITAL ORGANS OF D. CRASSICORNIS. D. DORSAL VIEW OF MALE GENI- 
TALIA OF THEREVA VIALIS. E. INTERNAL GENITALIA OF SAME, HIGHER MAGNIFICATION. 
acters may be found in this portion of the venitalia and in the 
gonopods (styles and lobes) attached to the hypandrium. These 
characters have been used very little in this paper, but ultimately 
