474 



PROCEEDINGS. 



October 17th, 1902. — Ordinary Meeting. 

 J. G. Waller, Esq., F.S.A., Vice-President, in the Chair. 



The minutes of the ordinary meeting of June 20th, 1902, were 

 read .and confirmed. 



The donations to the Library were announced, and the thanks 

 of the Club voted to the donors. 



A paper was read by Mr. W. H. Harris on " The Dentition 

 of the Diptera," illustrated by a large number of photographs 

 shown upon the screen. 



Mr. Hilton inquired if there was any good ground for regard- 

 ing the organs described as teeth. He thought they might be 

 very useful as a means of classification ; but had they ever 

 been observed in such action as to justify the name of teeth ? 

 They might also be very useful to the insect for screening its 

 food, as suggested ; but this in itself would not constitute them 

 teeth. 



Mr. Wesche expressed his admiration of the illustrations 

 shown, but thought that most of the facts had been already pub- 

 lished in '^ Science Gossip." He inquired if Mr. Harris found 

 that the teeth communicated with the main trachea and were 

 used for sucking. 



Mr. Harris said he thought that this was not so. 



Mr. Wesche said he was sure that the sucking had nothing 

 whatever to do with the teeth, which were placed in the middle 

 of the labellae. It was stated by Professor Packard that the 

 teeth were used for scratching, and that the edges and backs of 

 books were sometimes damaged by means of them. As to the teeth 

 being used in killing prey, he thought that that was a mistaken 

 idea. The hypopharynx, the lancet, under the labrum, was used for 

 that purpose. Mr. Harris seemed to be under the impression that 

 the pseudo-tracheae were the only organs of suction ; and as to the 

 homology of these organs he had said nothing. Later obser- 



