1967] 
MacLeod & Adams — Berothidae 
247 
ing so narrowed that a condition has been reached where there seems 
to be only a single sclerite (figs. 10, 1 1 , gs. gcx). The presence of 
setae on this structure provides confirmatory evidence of its composite 
origin since in our experience the gonarcus rarely bears setae while 
the gonocoxites usually do. 
The free, distal portion of the mediuncus frequently undergoes 
extreme elongation in different groups of berothids, producing an 
attenuate structure which may be further increased in length by the 
presence of long setae at its distal end. This elongate organ is carried, 
in the manner of a coiled watch spring, in a reflected internal pocket 
of membranous cuticle. The male of Naizema mendozina which we 
have illustrated (figs. 21, 22) illustrates a moderate development in 
this direction. Tjeder (1954) has applied the term “penisfilum” to 
such specialized mediunci. At the opposite extreme, species of Lo- 
mamyia have the distal portion of the mediuncus reduced so that 
only the basal sclerite in the dorsal wall of the ejaculatory duct re- 
mains (figs. 10, 11, 12, mu). In this genus a distal tuft of fine, 
short setae with specialized tips is present without any elongation of 
the mediuncus (fig. 12). 
The system of homologies we have used for the external female 
genitalia is based upon an extensive study of neuropteran genitalia, 
which will be published elsewhere. A large 8th sternite, bearing 
setae, is readily identifiable in most Sialodea and many Planipennia. 
Explanation of Plate 33 
Cyrcnoberotha penai n. sp.: Figs. 14-17, based on several $ paratypes. 
Lomamyia flavicornis (Walker), $ : Figs. 18-19, drawn from a specimen 
from Washington, D. C., Rock Creek Park; 10 June 1958 (M58-25#10); 
E. MacLeod Col. ; in MacLeod collection. 
Fig. 14. Detail of internal genital anatomy, lateral view, showing connec- 
tions of median oviduct, spermatheca, bursa copulatrix and colleterial gland. 
External cuticle depicted as in median longitudinal section. Fig. 15. Ventral 
view of terminal abdominal segments. Genital chamber, depicted as seen 
when 8th gonocoxites are drawn anteriorly away from 9th gonapophyses. 
Fig. 16. Terminal abdominal segments, lateral view. Fig. 17. Spermatheca. 
Fig. 18. Terminal abdominal segments, lateral view, genital chamber de- 
picted as opened slightly by posteriad retraction of ventral process of fused 
9th tergite + ectoproct from its usual articulation against posterior end of 
8t,h sternite. Fig. 19. Same, ventral view. 
Abbreviations: a — anus; cal. cere. — callus cercus ; coll. gl. — colleterial 
gland; com. ovd. — common oviduct; cop. b. — bursa copulatrix; ect — 
ectoproct; egg — mature oocyte in lateral oviduct; fert. c. — fertilization 
canal; 8gcx, 9gcx — 8th, 9th gonocoxites; 9gph — 9th gonapophysis ; gpr — 
gonopore: exit of median oviduct into genital chamber; 7S, 8S, 10S — 7th, 
8th, 10th sternites ; sp — spermatheca; sp. d. — spermathecal duct; 8T, 9T 
— 8th, 9th tergum ; 9T+ect — fused 9th tergite and ectoproct. 
