THE CANADIAN ENTOMOLOGIST 109 



and the latter a hyperparasite. A number of parasitized pupae 

 were noted but they were not e\idently abundant enough during 

 the past season to form any appreciable check on the insect. 



At Paterson, N.J., a number of rather small pupcC were noted. 

 As they were late in developing and undersized it was thought that 

 development might have been affected by parasitism. This proved, 

 howe\er, not to be the case, as beetles were reared from practically 

 all that were collected. 



In addition to the parasites a predaceous bug was observed 

 attacking this insect. An adult beetle was found with three 

 nymphs of a species of Heteroptera attached to it. One had the 

 lancets of the beak inserted at the left eye, a second at the tibio- 

 femoral articulation of the left posterior leg, and a third between the 

 last and the preceding ventral segment. At other times dead 

 larvae were noted and it may be that these also had been attacked 

 1)y a similar predaceous species. 



Owing to the fact that Lina scripta Fab. is found associated 

 with this species it is interesting to note some differences between 

 the two. Differences in the glands occurring in the larvae have 

 already been mentioned, but the larvae also differ in that L. scripta 

 Fab. is somewhat darker than P. versicolora and of course attains a 

 larger size. The resulting pupa is also larger than that of P. 

 versicolora and hangs from the lower surface of the leaf, attached 

 onl\- at the anal end of the bod\-. The eggs of L. scripta Fab. are 

 somewhat similar but the mass is somewhat larger and composed 

 of a larger number of eggs, 60 to 70 having been observed in some 

 masses, while the individual egg is larger and of a light lemon-yellow 

 colour. 



Explanation of Plate VII. 



Fig. 1. Egg. 



Fig. 2. Small egg mass. 



Fig. 3. Fifth stage larva. 



Fig. 4. Dorsal view of pupa with wing-pads slightly extended. 



Fig. 5. Adult, Plagiodera versicolora. 



Fig. 6. Lombardy poplar leaf, showing beetle feeding. (Photo 

 by H. Hornig.) 



Pig. 7. Willow foliage injured by beetles and larvae. 



Fig. 8. Lombardy poplar leaf, showing larvae feeding. (Photo 

 by H. Hornig.) 



