1963 ] 
MacLeod — Sympherobius 
65 
lighter, which is due principally to the rather greasy condition of the 
specimen. The interantennal mark and the pale undersurface of the 
antennal scapes are both visible with only slight difficulty in the type. 
The wing venation and maculation of the new specimens depart in 
no significant regard from the condition found in the holotype and 
described and figured by Carpenter (1940) except that the gradates 
and other cross veins have a narrow fuscous margin, this being par- 
ticularly evident with the two lower inner gradates and the MP-CuA 
cross vein. 
Description of abdominal terminalia (based on three male and four 
female specimens, cleared and in glycerine) — Male abdomen (PI. 6) 
with segments one through eight showing no unusual specializations. 
Ninth tergite ventrally produced and ending in a sharp postero- 
ventrally projecting point; posterior and ventral margin with a 
darkly sclerotized rim; ninth sternite ( PL 6, Fig. 1, 2, 6; IX) form- 
ing the usual subgenital plate characteristically present in Symphero- 
bius, projecting a little beyond posterior margin of ectoprocts 1 , broadly 
membranous dorsally, and appearing as a nearly equal-sided triangle 
when seen from above (PI. 6, fig. 6). 
Ectoprocts as in PL 6, fig. 1, 2, 3 (epr), consisting of a somewhat 
dumbeil-shaped, darkly sclerotized central area bounded by a more 
transparent area anteriorly and posteriorly; the dorsally sclerotized 
portion with the usual callus cerci bearing about ten trichobothria, 
the ventrally sclerotized portion below the constriction much smaller 
and somewhat convex, this convex lobe continuing posteriorly and 
anteriorly into the unsclerotized areas of the ectoproct; anteriorly, 
this lobe is covered by numerous regularly arranged fine punctations in 
the nearly transparent cuticle before the sclerotized ventral portion 
of the ectoproct; a single very dark, posteriorly directed spine arises 
from a paler linear basal plate in the constricted region of the sclero- 
tized area of the ectoproct. Gonarcus (PL 6, fig. 2, 4, 5 gs) narrowed 
posteriorly in lateral view with a large, ventrally directed portion 
(entoprocessus of Tjeder’s terminology) near the anterior end; 
arcessus (PL 6, fig. 4, 5 ar) rather thick in lateral view, beset beneath 
with numerous small microtrichiae. Parameres (PL 6, fig. 6, 7 pa) 
fused for nearly their entire length, separate only posteriorly, with 
the tips of the anteriorly directed middle arms unexpanded and with 
the fused portion showing little or no indication of a tooth in lateral 
view. 
The terminology used to describe the genital structures is that of Tjeder 
( 1954 ). 
