150 General Notes. [February, 



no insect of that order having such habits. I thought of the gre- 

 garious habits of Sciara, and wondered if I had not found some 

 new form which carried the larval custom on into the pupa state. 

 My friends were equally puzzled with myself— none had ever 

 seen such an object before. 



One day I found that a number of small Chalcids had issued 

 from one of the chains. This, however, did not shake my belief 

 as I considered the Chalcids as simply parasites upon the origi- 

 nal makers of the chain, and I waited with impatience for the real 

 owner. However, more and more of the Chalcids issued, until at 

 last every specimen I had collected, with the exception of those 

 put away in alcohol, had excluded ten or a dozen of the parasites, 

 and I had made up mind that I should have to wait till the next 

 season before solving the problem, the idea never striking me that 

 I had the solution right before my eyes. 



The next spring I bred from a mine of Gelechia pinifolia Cham., 

 a few specimens of a closely allied Chalcid and, upon opening the 

 mine from which they had issued, I found one of the familiar 

 chains, in which, however, the individual " puparia " seemed more 

 fused together, and an examination with a Tolles J^th showed a 

 delicate membrane surrounding them all. This membrane the 

 compound microscope showed to be the true skin of the Gelechia 

 larva, but so stretched as to leave the sutures perfectly indistin- 

 guishable and to be recognizable only from the spiracles and anal 

 hairs. Now going back to my oak chains I found, of course, the 

 same to be the case ; but the skin of the Lithocolletis larva had 

 shrunken down into the crevices so tightly and its surface was so 

 smooth that the resemblance to a string of puparia was perfect. 



Later I had the opportunity of examining a larva of Anarsia 

 lineatella Zeller, parasited by an allied species, and the same ap- 

 pearance resulted, greatly modified, however, by the larger size ol 

 the host and the greater thickness of its skin. I remember see j 

 ing somewhere a statement by Dr. Lintner, to the effect that he 

 had bred a very interesting parasite from this Anarsia, and I 

 hazard a guess that this was the species. I saw at once from this 

 last larva that the appearance which had puzzled me so was after 

 all only a modification of a phenomenon often met with in larger 

 larvae, the minute size of the Lithocolletis larva and the extreme 

 delicacy of its last skin combining to produce the curious effect. 



A somewhat similar appearance, caused by an allied parasite in 

 the rather large larva of Gelechia gallce-solidaginis, is described by 

 Professor Riley in his First Missouri Report. He calls the para- 

 site popularly " the Inflating Chalcis," and figures the parasited 

 larva at Fig. 5, Plate 2. 



Moreover, many attempts which were made last season to carry 

 through the larva of Plusia brassiae were frustrated by a congeneric 

 parasite with similar habits. The Plusia larva, up to the time of 

 commencing to spin, appeared quite healthy, although perhaps a 



