STATE AGRICULTURAL SOCIETY. 
853 
THREE-SPOTTED CEPHUS. DESCRIPTION OP TIIE FLY. 
No American representative of the genus Janus has hitherto 
been described, that I am aware, and the few European species 
pertaining to it are rarely met with by collectors. As the color 
of its hind body distinguishes our insect from the other known 
species of this genus, it may most appropriately be named the 
Yellow-bellied Janus, J. flaviventris. 
A kindred but larger insect, of which a pair found in Pennsyl¬ 
vania, were described by Mr. Say under the name Cephus trimacu- 
latus, occurs in New York also, making its appearance the fore 
part of June. This insect has the aspect of a very slender Tremex 
with the abdomen compressed as in Ophion. Its antennae aro 
27-jointed ; hence it pertains to the genus Phyllcecus of Mr. New¬ 
man. These organs are thickest in their middle and taper insen¬ 
sibly towards each end, the sub-basal joints being less than half 
the diameter ot the middle ones, and cylindric. The third joint 
is four times as long as thick and is slightly curved, and the 
fourth joint is a third shorter. 
this insect is black with a small white spot on each side of 
the middle of the hind body and a larger egg-shaped one on its 
base, from which spots it has received its name. The orbits or 
edges of its eye sockets have a white dot above and a white 
streak below the antennae sockets, and the mandibles aro dull 
white, except at their tips. Its wings are smoky-violaceous and 
transparent. In the second cubital cell is a black dot, placed 
near the anterior end of its inner margin; and the vein, from 
this dot to the anterior end of this cell, is margined on each sido 
with a short white line. The anterior inner discoidal cell has a 
smoky spot on the middle of its hind side. Most of the middle 
and posterior veinlets have a white band on their inner or on 
both their ends. The male varies in length from 0.48 to 0.55, 
and the female is a third larger. 
