affecting the Corn-Crops. 
509 
was a saw-fly called Selandria humeralis,* of which there were 
several ; another was a beautiful little green parasitic fly with 
black feet, which was running over the ears; it belongs to the 
family Chalcididce, and is an Entedon.\ The third was so abundant 
that Mr. Graham took many of them on the wing ; and as, in all 
probability, it lives upon the larva of some insect infesting the corn 
I will describe it. It is related to the species lately alluded to in 
this Journal, which is parasitic on the Chlorops tcetiiopiis ; l it 
consequently belongs to the Order Hymenoptera, the Family 
IcHNEUMONiDES ADSCITI ; and forms a portion of the Genus Dac- 
NUSA, I beheve,§ and being uncertain of its specific name, I pro- 
pose calling it, from its inhabiting corn-fields, 
13. Dacnusa cerealis : Male, slender, black, and shining; head 
rather small and subglobose ; eyes orbicular; ocelli 3 in triangle: 
antennae as long as the body, filiform, composed of 21 joints, pube- 
scent and fuscous, the three or four basal joints bright ochreous, 
first joint oval, truncated obliquely; second, small, globular ; third, 
long; fourth, and following, decreasing in length : thorax elongated, 
gibbose before; scutellum rugose with elevated lines, the sides 
striated; postscutellum rugose, with three elevated lines forming a 
trident on the back ; the pedicle is elongated, narrowest at the 
base, depressed, striated, and pitchy-brown ; abdomen rather short 
and slender, the apex clavate, brown, excepting the basal joint, 
which is ochreous-brown, and the belly is of a similar but a paler 
tint: four wings very transparent, beautifully iridescent, nervures 
very pale reddish-brown, as well as the stigma, which is elongated ; 
radial cell perfect and reaching to the apex : two complete discoidal 
cells, all the posterior ones imperfect : legs long, slender, and bright 
ochreous; tarsi 5-jointed, their tips and claws black : length \^ 
line, expanse 3 lines. 
Corn-Bugs. 
We have now arrived at some insects belong in^; to the CimicIdtE 
or tribe of bugs, which are abundant in corn-fields, and probably 
live upon other insects that injure the crops. Mr. Kirby describes 
one in the Linnean Transactions,i| which he found very common 
upon the wheat, in all its states, with the wheat-midge, but he 
could not discover that it devoured it. Tiie larvae, pupa?, and 
perfect insects were at the same time upon the straw and ears ; for 
like the plant-lice or Aphides, this tribe is active, and resembles its 
* It belongs to the Tenthredinida;, and is nearly allied to the At/ialia spt- 
narum produced from the Nigger Caterpillar ; Royal Agric. Jour., vol. ii 
p. 364. 
t Curtis's Guide, Gen. 620. 
X Calinim niger, Royal Agric. Jour., vol. v. p. 496. 
§ Haliday"s Hymen. Brit. Fasciculus, ii. p. 5. 
II Vol. v. p. 110. 
2 M 2 
