398 



Records of the S.A. Museum 



readily maintained in aquaria upon a diet of mosquito larvae. Anisops impar- 

 tially inhabits running or stagnant water, clear or muddy. Examples taken from 

 the River Murray lagoons, and others from Broken Hill, New South Wales, are 

 at times infested with an Hydrachnid parasite, which also occurs on Corixids and 

 water-beetles. Seldom more than one parasite is present on a small bug, whereas 

 several are commonly attached to one beetle ; the mite is usually fastened to the 

 pronotum of the bugs, more rarely to an eye. 



Vertex 



V\g. .16]. Noineiielatiire of dorsal 

 surface of head. 



Fijr. .362. Head of Animipa Jiyjirrion as seen from hclow: 

 (■(•) fliitiiioiis i)roiios of beak; (s) femoral stridu- 

 latory coml). 



With a view" to determining in some measure the periods at which the various 

 aquatic bugs occur at Adelaide, the ponds bordering the River Torrens w^ere under 

 observation during two successive years. In these situations the backswimmers 

 disappeared at the end of the autumn, but Corixids were taken throughout the 

 year, hibernating females being found amongst masses of Nitella and Chara in 

 the cold months. On the other hand, in mid-Avinter many Anisops, including four 

 species, were collected at Broken Hill from dams which had been almost or quite 

 dry during the latter part of the summer. 



The life history and biology of Anisops have not hitherto been recorded : an 

 account of Anisops hyperion is given on page 405. 



Excepting for the deposition of eggs, Anisops very rarely clings to plant 

 stems, its poise in the water being almost perfect ; Enithares commonly anchors 

 itself to submerged objects (see pi. x, fig. 1), even walking up a plant stem to 

 the surface for a rencAval of its air supply. 



Reproduction. From an examination of the gonapophyses of the females 

 of six Australian sjoecies of Anisops it is evident that at least these members of 

 the genus insert their eggs in plant tissues. The endophytic oviposition of 

 A. hyperion was proved by actual experiment, and a comparison of the drilling 

 gonapophyses of this species with the others figured on pi. xi will show that, 

 without doubt, all serve a similar purpose. 



