TflE VICTOIIIAN NATURALIST. 



past times. May one or the other theory be accepted or not by 

 a severe critic, so much is certain, that even an insignificant 

 contribution on the subject will be gladly received, so that it may 

 be used as a stone in the building which our forefathers have 

 begun, which we in our turn have inherited, and which our 

 generation ought to be proud to continue and complete. 



ON THE OCCURRENCE OF THE MOSQUITO 

 ANOPHELES IN VICTORIA. 



By J. A. Leach. 

 (Bead before the Field Naturalists' Club of Victoria, lith March, 1904.) 

 While attending to my duties as nature study teacher under the 

 Education Department, my attention was attracted by a mosquito 

 larva which persisted in remaining at the surface of the water. 

 Suspecting an Anopheles larva, it was examined microscopically, 

 and proved to be identical with the larva figured in Theobald's 

 " Monograph of the Culicidae of the World " as that of Anopheles. 



Its horizontal position when floating at the surface, its habit 

 of shooting oft" horizontally when disturbed, the very short 

 breathing tube with its two spiracles, the peculiar branching hairs 

 on the thorax and abdomen, the remarkable " dorsal organs," 

 five pairs of stellate hairs on the top of the abdomen, the strange 

 appendage with long branching hairs on the last segment — these 

 features, so striking, left little doubt as to its being the larva of 

 an Anopheles. 



One strange habit, mentioned by Howard in his very in- 

 teresting and valuable work entitled " Mosquitoes," viz., that of 

 floating with the under side of the head uppermost, and then 

 rotating it at intervals, apparently to swallow, was often seen. 



More larvae were collected from the same place — a pot-hole in 

 the path on the north side of the Zoological Gardens. On the 

 surface of the water in this small hole were over a dozen egg-rafts 

 of Culex, while hundreds of Culex larvae hung head down, or 

 moved actively about. Twelve Anopheles larvae were taken on 

 this visit. 



The dorsal organs or stellate hairs were found to vary in 

 number. Generally five or six pairs were present. Their 

 function seems to be unknown, but, as the result of close 

 observation, it seems probable that they assist the larva to 

 maintain the horizontal position, by holding on to the skin of 

 the water. 



Professor Spencer, under whom I have had the honour and 

 privilege of working for some tirrie as a science student, advised 

 me to allow these larvse to develop to the adult state. Soon 

 several pupated, forming a pupa somewhat similar to that of 



