io6 



TRANSACTIONS OF THE ILLINOIS 



lines generally cover the whole abdomen.) Ovipositor longer than abdomen, but 

 when stretched in a line with it, projecting backwards about the same length 

 beyond; ntfous, with the sheaths black. Lc^s. pale rufous with the upper part of 

 hind tibia? and tarsi, and sometimes the hind femora, dusky. Wi'/iffs subhyaline 

 and iridescent, the veins pale rufous and the stigma black. Length female 0.15- 

 0.16 inch, expanse 0.30; male differs only in his somewhat smaller size and in 

 lacking the ovipositor. In many specimens the mesothorax and the eyes are more 

 or less distinctly rufous. 



Described from 50 females, 10 males bred June 23d — July 29th 1S70 from larvae 

 of Conotrachelus 7ienufhar, and 2 females obtained from Dr. Fitch. 



Larva, (Fig. 5, a) — white with translucent yellowish mottlings. 



Pufa, (Fig. 5, c) — Female — 0.17 inch long; whitish, the members all distinct, 

 the antennae touching hind tarsi, the ovipositor curved round behind, reaching and 

 touching with its tip the third abdominal joint, which afterwards forms the apical 

 joint of imago; five ventral joints, which in the imago become much absorbed and 

 hidden, being strongly developed. 



Cocoon, (Fig. 5, h) — Composed of one layer of closely woven yellowish silk. 



VARiETi- RUFUS — Head, thorax and most of first abdominal joint entirely rufous, 

 with the middle and hind tibice dusky, and the ovipositor three times as long as 

 abdomen and projecting more than twice its length beyond its tip. 



Described from three females bred promiscuously with the others. This variety 

 is slightly larger and differs so remarkably from the normal form that, were it not for 

 the absolute correspondence in all the sculpturing of the thorax and body, and in 

 the venation of the wings, it might be considered distinct. The greater length of 

 the ovipositor is very characteristic and accompanies the other variations in all 

 three of the specimens. 



LFlGURK 6.] 



Porizon Curculio Parasite : {a) female ; {h) male ; (c) antenna. 



The other parasite works in very much the same manner btit 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 discovered by Dr. Trimble who sent me the cocoons from which I 

 subsequently bred the perfect fly. It belongs to the first sub-family 

 {Ichneufnonides) of the Ichneumon-flies and apparently to the genus 

 Porizon'^ of which it forms a new species. But I shall here also, in this 



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

 classification of the Ichneumonid.^, it might more properly he referred to Holmgreu's genus 

 T hersiloclms which differs from Porizon in the greater distance between the antenna; at base, and 

 in the venation of the wing. 



