BY R. J. TTLLYARD. 281 



enlarged, contiguous procoxfE, are all shown in position, viewed 

 from in front, in Plate xii., fig. 2. 



Type in Coll. Tillyard. {^, Stradbroke Island, September 

 20th, 1915). 



//a6.— Stradbroke Island, S. Queensland. Two males taken 

 on September 20th, 1915; one beaten out of a cypress-tree, 

 another found resting on reeds in a swamp. 



The following note on this species may help to throw some 

 light on the question of whether Ithone is an aquatic genus or 

 not. The town of Dunwich, on Stradbroke Island, is supjjlied 

 with water from two large tanks, set high up on the side of a 

 hill. Water is pumped from a perennial stream near the coast, 

 about two miles distant, by means of a pipe-line, which discharges 

 into tank A. Tank B is connected by a base-pipe, so that its 

 level rises with that of A, but it receives no water direct from 

 the pipe. When returning with Mr. H. Hacker, of the Queens- 

 land Museum, on September 21st, 1915, on our way to Dunwich 

 to catch the steamer for Brisbane, we took the track up the hill 

 to the Tanks. As the day was very hot, on arriving at the 

 Tanks we stopped for a rest, and Mr. Hacker climbed the ladder 

 placed between the tanks, in order to drink the cool water dis- 

 charging into tank A. On looking into tank B, he noticed a 

 large number of Ithone lying dead on the surface of the water, 

 and called my attention to them. I ascended the ladder, but 

 found that the depth of water in the tanks was so low (owing to 

 the prolonged drought) that it was quite impossible to reach any 

 of the Ithone with ray net; also, they were all very much spoilt, 

 and not worth securing as specimens. I noted, however, that 

 they were of both sexes, and all appeared to be of a pale colour, 

 as if newly emerged, while, in some cases, the wings were badly 

 crumpled. In tank A, where the water was disturbed by the 

 jet from the pipe, I did not notice any Ithone at all. 



Now the question is, did all these Ithone fall into this tank 

 and get drowned, while flying at night-time, either by pure acci- 

 dent, or perhaps because they are attracted by water ? Or did 

 their larvse actually live in the still waters of tank B, and the 

 imagines fail to escape on emerging, owing to the lack of reed- 



