110 ENTOMOLOGICAL SOCIETY 



it might be due in part to the excretory products of the insect. 



Mr. Schwarz asked Mr. Cook whether he considered all galls 

 injurious to the plants on which they occur, citing as cases 

 which he did not consider injurious such leaf-galls as did not 

 cause the leaves to fall off earlier than those leaves not in- 

 fested. He gave also another case, namely, the Blastophaga 

 galls in the fruits of Fiats carica, where the insects were 

 necessary to the propagation of the plant. Mr. Cook replied 

 that, while galls are often very injurious, it did not follow that 

 in all cases they are materially so, but he did not think them 

 often beneficial. 



— Doctor Howard, apropos to the discussion on galls and to 

 Professor Froggatt's remarks at the preceding meeting, called 

 attention to an article by Dr. Gustav Mayr in the Verhand- 

 lungen der k. k. zoologisch-botanischen Gesellschaft in Wien 

 for December 30, 1905, in which a remarkable gall made by 

 a perilampine on the leaves of Acacia pendula sent him by 

 Professor Froggatt from Australia is described. Doctor 

 Howard stated that the Perilampinae had previously been con- 

 sidered as purely parasitic forms, but that this insect described 

 by Mayr as Trichilogaster pendnlcc is undoubtedly a true gall- 

 maker, and is very remarkable in that its gall contains two 

 chambers — one, a large central chamber from which a female 

 emerges, and the other a small peripheral chamber from which 

 a single male emerges. Mayr suggests that the mother female 

 lays two eggs, one female and the other male, and, since the 

 female larva causes the formation of the globular gall, the 

 male larva has to be satisfied with a more external gall. 



— Professor Webster presented the following paper: 



THE FASHIONING OF THE PUPAL ENVELOPE IN 

 LYSIPHLEBUS TRITICI ASHM. 



By F. M. Webster. 



(Plate VI.) 



Most insects with a complete metamorphosis, in view of 

 their helplessness while passing from the larva to the adult, 

 provide for their protection during this critical period by the 

 construction of various forms of cocoons. Such as pass this 



