400 The Ohio Naturalist. [Vol. XII, No. 1, 



The only particular enemy noted is a small Ichneumonid 

 parasite (Bassus sp.) which oviposits through the skin of the larva. 

 The parasitic larva does not prevent the formation of a more or less 

 complete puparium, but emerges as adult about four weeks after 

 pupation of host by gnawing a small irregular hole in the anterior 

 end of the puparium (see Fig. 3G). The first indication of the 

 presence of the parasite is usually a failure of the pupal envelope 

 to inflate completely, remaining less rounded up dorsally and often 

 with the anterior segments but little retracted ventrally. Very 

 soon the pupa becomes darker in color than normal, in this species 

 becoming purplish instead of testaceous brown. These char- 

 acters should be easily told and one with a very little experience 

 might do great good by destroying all such parasitized pupae 

 before the hymenopteron has time to emerge. 



Pupa. 



Dimensions, average of ten: Length 5.3 mm., height 2.2 mm., 

 width 2.4 mm. Pupation takes place within the indurated 

 larval skin which becomes inflated dorsally and anteriorly, 

 retracted ventrally so that the mouth comes to lie well back on 

 the ventral side. As seen from above (Fig. 27) the puparium is 

 near oval in outline but with sides somewhat straightened and 

 with the breathing appendages giving a more extended outline 

 posteriorly. From in front the puparium is almost circular in 

 outline. As seen from the side (Fig. 28), the ventrum is nearly 

 straight, dipping down slightly anteriorly and posteriorly, thence 

 rounding up strongly to the dorsum. In many specimens the 

 anterior end of the larva has been more strongly retracted ventrally 

 and the anterior and posterior ends more equally rounded up 

 than is shown in Fig. 2S. 



The color varies from brown-pink to darker sometimes with 

 obliquely transver.se banding of testaceous brown and blackish. 



The long segmental spines contrasted with the short-dorsals, 

 or their apparent absence on the principal segments, and the 

 short posterior respiratory appendage with its prominent spoon- 

 shaped spurs at the end, dorsally, should serve easily to identify 

 the species. 



Date of pupation: Columbus, June 6th and later; Lakeville, 

 June 23 to 26; Sandusky, July 3 and later; Kelley's Island, Lake 

 Erie, July 8 to 13. The duration in the pupa stage was from 

 5 to 15 days with the majority about 12 days. 



The pupae are to be found lodged and fastened among the 

 flowers in the spike and the axils of the leaves, or on the upper 

 side of the leaves of the host plant. They are stuck to the leaves 

 by their posterior end. Protective coloration may be of some 

 importance to the pupae as well as to the larvae. 



The adult emerges by pushing off a circular operculum from the 

 anterior end of the pupa-case. 



