1880.] 391 [Patton. 
anterior portion with a broad median impression on each side of 
which is an impressed line. Metathorax abruptly truncate, the sides 
and upper surface uniformly and finely granulated, the posterior face 
limited above by a transverse ridge beneath which is a deep 
elongated depression in the median line, on each side of this the 
posterior face delicately rugose transversely. Anterior tarsi strongly 
ciliate, the bristles exceeding the second joint of the tarsus in length. 
Wings subhyaline, tegulae and nervures black or piceous; marginal 
cell obliquely truncate as in distincta (Sm.), indistinctly appendicu- 
late; recurrent nervures distant at their insertion into the second 
submarginal cell, more distant than in distiéncta and much more so 
than in argentata Beauv. Area on sixth segment of the abdomen 
narrow and pointed, glabrous, margined, its disk sometimes sparsely 
punctured. 
Waterbury, Conn., Aug. 20th, 21st and 24th. 
In size and color acuta bears much resemblance to the black males 
of distincta. It is related to terminata, tarsata and mentana. 
TacHYTES Panz. (1806). 
Syn. Lyrops Illiger (1807). 
Type of Panz. and Ill.: species with dentate mandibles. 
Type of Westwood (1840) : pompiliformis Pz. 
The type pompiliformis has a distinct appendiculation to the 
marginal cell. Other species having no appendiculation to the 
marginal cell may require to be set apart, and as etrusca, the type of © 
Lyrops Ill., is one of these, the name Lyrops might be adopted for 
the new genus. But as the name Lyrops of Illiger has properly 
passed into synonymy, the present date and not Illiger’s should be 
quoted. Dahlbom in 1843, however, established a new group 
Lyrops with pagana as type (the Lyrops of Illiger being at that time 
obsolete) and proposed the name Tachyptera for the species without 
appendiculation, with obsoleta as type. It may be well, therefore, to 
let Lyrops share the fate of pagana and adopt Tachyptera with 
obsoleta as the type, notwithstanding that obsoleta is strictly congeneric 
with etrusca, the type of Illiger’s Lyrops. 
Some of the species here referred to Zachytes may need, there- 
fore, to be called Tachyptera or Lyrops, and most of those referred 
to Larra may require the formation of a new genus (and for this 
new genus the name Larrada, n.g. nec. Smith, would be con- 
venient); but I do not at present find sufficient characters for 
