SMULYAN: NEW ENGLAND TENTHREDELLA. 395 
posterior angles on top of the ridges between the metascutum 
and meta-postscutellum, to the base of the hind wing, and these 
continuations will be termed metascutel transverse extensions. 
The meta-postscutellum, the postnotum of Snodgrass (1910), 
extends transversely across the whole of the dorsal surface. It 
is much wider than long, almost vertical, and somewhat bulged 
medially and longitudinally. It is bounded anteriorly by the 
metascutellum and metathoracic sinuses; behind, it articulates 
with the first abdominal segment. 
The .meta-epimeron is smaller than the meso-epimeron, but 
similar in outline, — plano-convex. It lies immediately above 
the diamond-shaped meta-episternum. 
The term meta-episternum will be applied to only a portion of 
the episternum of the metathorax, viz., the visible lateral, dia- 
mond-shaped portion which is bounded by the meso-epimeron in 
front, by the meta-epimeron above, by the posterior coxa behind, 
and by the intermediate coxa below. The remainder of the 
meta-episternum lies on the ventral surface, where it has fused 
with the metasternum, and cannot, as a rule, be seen, being masked 
by the intermediate and posterior coxae. 
The thorax, like the head, is quite densely clothed with very 
fine, short, more or less erect silvery hairs. Its surface, too, is 
more or less roughened with punctures and striations. The meso- 
episternu'm is sometimes quite rough [grandis (Norton)]. The 
punctures on the prescutum are, as a rule, finer and denser than 
on the mesoscutum; sometimes, however [cogitans (Provancher)], 
they are very minute and dense on both. The post-tergite is, as 
a rule, coarsely punctate. 
Abdomen. 
The sessile and cylindrical abdomen ends acutely in the female 
(PI. 4, fig. 2) ; in the male it is slightly rounded off on each side 
at the apex (PI. 4, fig. 4). In pinned and dried specimens, it is 
more often dilated and flattened, owing to the relaxation of the 
muscles. This is especiallj^ true of the abdomen of the female 
which as a consequence very frequently appears more or less oval 
in outline. The upper or dorsal surface consists of nine distinct 
segments or terga, although the last or ninth tergum in the female, 
when it is sufficiently exserted, shows a faint transverse line of 
