160 PROCEEDINGS ENTOMOLOGICAL SOCIETY 



by the scent left by the parent moth on the leaves on which she 

 oviposits. At about this time a larva of A. clarescens about one- 

 third grown was found. This was placed in the cage with the para- 

 sites. They seemed to be interested only in avoiding it. 



A few days later some of the Apatela eggs hatched. The newly 

 hatched larvae were exposed to the attack of the parasites and were 

 almost immediately attacked, the parasites fairly pouncing upon 

 them. During the act of oviposition the host larva is beneath the 

 parasite, whose ovipositor is extended forward and inserted in the 

 side of the host. Subsequently caterpillars of various sizes up to 

 a third of an inch in length were exposed to the attack of the para- 

 site, but in no case was any except newly hatched or very young 

 caterpillars attacked. All larvae that were attacked by the para- 

 site were isolated and fed in order to obtain further data on the 

 life history of the parasite. Most of them died while very young, 

 while those that lived produced only moths, so that there is only 

 negative proof that the attack observed in the cages is the natural 

 one. 



At one time during the progress of the experiments with X. 

 bicolor a large number of living females were confined together in 

 one cage, which was placed against the screen of the insectary. 

 Several males of the species were captured on the outside of the 

 insectary, having evidently been attracted by the scent of the 

 females. 



-In the discussion of Mr. Cushman's paper, Dr. Hopkins called 

 attention to a reference in an early number of Insect Life (III, p. 

 20) to his observation on the parasite, .Perilitus, of the adult of 

 Hippodamia maculata, and the evidence found by him that the 

 parasite larva emerged from the ventral part of the body, through 

 the suture between the abdomen and metasternum. 



Dr. Hopkins also mentioned, in this connection, the common 

 occurrence of parasitized adults of Scolytid beetles, especially 

 those of the genus Ips. The parasite (Tomicobia tibialis Ash. det. 

 Ash.) oviposits through the elytral suture and the adult emerges 

 through a round hole in the declivity. Dead or living adults arc 

 often found in the insect boxes, having emerged after the beetles 

 were mounted, on card points. 



-Dr. Howard said that work of the character just described 

 by Mr. Cushman was of very great value. This and similar work 

 carried on by Mr. Timberlake, and which also related to the in- 

 timate life history of parasitic insects/ has much potential prac- 



