42 THE REPOET OF THE No. 36 



The Society's cabinets contain a very complete collection of the Lepidoptera 

 and Coleoptera of the Provinces of Ontario and Quebec and a good number of 

 representatives of the other orders. In addition there are many very beautiful 

 specimens of exotic Lepidoptera. 



The Branch Associations connected with the Society are doing excellent work. 

 They spread the knowledge of economic entomology to the great benefit of the 

 farmers, horticulturists, and fruit-growers, in their several localities. 



EVEN"ING SESSION— THURSDAY, NOVEMBER 3rd, 1910. 



A public meeting was held at 8 o'clock p.m. in the Massey Hall Auditorium, 

 at which there was a good attendance of students and representatives of the College 

 staff, as well as of members of the Society. The chair was taken by Mr. C. C. 

 James, Deputy Minister of the Ontario Department of Agriculture. The pro- 

 ceedings were enlivened by some musical selections given by members of the College 

 Philharmonic Societ3^ After a few remarks by the Chairman congratulating the 

 Society on reaching its forty-seventh annual meeting, and referring to the amount 

 of good work that it has accomplished, he introduced the speaker of the evening. 

 Professor James G-. Needham, of Cornell University, Ithaca, N.Y., who occupies 

 the chair of Limnology in the Department of Entomology. His subject was '' The 

 Role of Insects in Water-life," illustrated with many beautiful lantern pictures. 

 The following is an abstract of his remarks : — 



THE ROLE OF INSECTS IN WATER-LIFE. 

 Prof. James G. Needham {Abstract). 



Aquatic insects are not found in all the waters of the earth, but are mainly 

 restricted to shoal parts of fresh water and to the shelter of rocks and vegetation. 

 There are but few found inhabiting even the bottoms of our deeper lakes and 

 streams, a few blood worms, caddis-worms and the burrowing nymphs of May-fiies, 

 and there is but one, Corethra, that is strictly free-swimming in habits and a constant 

 denizen of the open water. Moreover, it is mainly the larval stages of insects that 

 are aquatic; only these breathe by gills, and the larvae are tied by parentage to the 

 shores. 



Alongshore, however, insects constitute a very important part of the sub- 

 merged population, being present often in inconceivably vast numbers. Sometimes 

 a species, like the great May-fly, Ilexagenia, that is synchronous in its habits of 

 transformation, comes forth in swarms that darken the air on a midsummer evening, 

 but the vast majority of aquatic insects are not thus concerted in habits and give us 

 no visible demonstration of their abundance. Yet they abound in all aquatic situa- 

 tions in shoal water. Some groups, like the stone-flies, are fitted for life in rapid 

 waters only, but most of the larger groiips, like the flies and the beetles and the 

 dragon-flies, contain representatives expressly adapted to situations of the utmost 

 diversity. The rapid-water forms are usually flattened and depressed in body for 

 attachment to the surface of stones where the water glides over them. And, on the 

 other hand, those in stagnant waters usually possess devices for protecting their 

 delicate gills from the accumulation of sediment. 



