28 



THIRD ANNUAL REPORT OF 



THE POKIZON CUUCULIO PARASITE. 



The other parasite works in very much the same manner, but 

 C Fi s- 9 -l instead of issuing the same summer as a 



fly, it remains in its somewhat tougher 

 and more yellowish cocoon all through 

 the fall and winter, and does not issue 

 ,in the winged state till the following 

 ^spring. This parasite was first discov- 

 ered by Dr. Trimble, who sent me the 

 cocoons from which I subsequently 

 bred the perfect fly. It belongs to the 

 first sub-family ( Ichneumonides) of 

 the Ichneumon-flies, and apparently to the genus Porizon* of which 

 it forms a new species. It is only necessary here to state that it 

 differs from the other species in its reddish-brown abdomen, as well as 

 in form, as may be readily seen by referring to the figures (Fig. 9, a 

 female; b male; c antenna). 



Porizon conotracheli, N. Sp. — Head pitchy-black, opaque, the ocelli triangularly placed and 

 close together ; eyes oval, polished, and black ; face covered with a silvery-white pubescence ; 

 labrum rufous, with yellowish hairs ; mandibles and palpi, pale yellowish-brown ; antennas in- 

 serted in depressions between the eyes, reaching to rnetathorax when turned back, filiform, 

 24-jointed; black with basal joints 6-1 becoming more and more rufous, the bulbus always dis- 

 tinctly rufous ; bulbus rather longer and twice as thick as joint 3 ; joint 2 about one-third as long. 

 Thorax pitchy-black, opaque, the sides slightly pubescent with whitish hairs, the mesothorax 

 rounded and bulging anteriorly, the scutellum slightly excavated and sharply defined by a carina 

 each side ; rnetathorax with the elevated lines well defined and running parallel and close together 

 from scutellum to about one-fourth their length, then suddenly diverging and each forking about 

 the middle. Abdomen glabrous, polished, very slender at base, gradually broader and much com- 

 pressed from the sides at the apex which is truncated ; peduncle uniform in diameter and as long 

 as joints 2 and 3 together ; joints 2-5 subequal in length ; color rufous with the peduncle wholly, 

 dorsum of joint 2, a lateral shade on joint 3, and more or less of the two apical joints superiorly, 

 especially at their anterior edges, black ; venter more yellowish: ovipositor about as long as ab- 

 domen, porrect when in use, curved upwards when at rest, rufous, with the sheaths longer and 

 black. Legs, including trochanters and coxaj uniformly pale yellowish-brown with the tips of 

 tarsi dusky. Wings subhyaline and iridescent, with veins and stigma dark brown, the stigma 

 quite large, and the two discoidal cells subequal and, as usual in this genus, joining end to end, 

 but with the upper veins which separate them from the radial cell, slightly elbowed instead of 

 being straight, thus giving the radial cell a quadrangular rather than a triangular appearance. 

 (5 1 differs from $ only in his somewhat smaller size and unarmed abdomen. Expanse $ 0.32 

 inch, length of body, exclusive of ovipositor 0.22; expanse $ 0.28, length 0.18. 



Described from 3 $ 2,1c? bred May 26th-28th, 1870, from cocoons received from Dr. I. P. 

 Trimble, of New Jersey, and 1 $ subsequently received from the same gentleman — all ob- 

 tained from larvae of Conotrachelus nenuphar. 



" But of what use are these parasites ?" say you ! Well, they can 

 not, it is true, be turned to very practical account, because they are 

 not sufficiently under our control; but it is a source of great satisfac- 

 tion to those who have been looking for many years for some natural 

 aid to help them in the artificial warfare waged against the Curculio, 



* As I am informed by Mr. E. T. Cresson, of Philadelphia, who pays especial attention to the 

 classification of the Ichneumonidm, it might more properly be referred to Holmgren's genus Ther- 

 silochus, which differs from Porizon in the greater distance between the antenna? at base, and in 

 the venation of the wing. 



