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DR. A. INGRAM NOTES ON THE MOSQUITOS OBSERVED 



Placed in a glass vessel containing water and the water-plant from their native 

 pool the larvae may be watched attaching themselves by their siphon-tubes to the 

 roots of the plant below the surface of the water. Having attached themselves 

 they will remain under water for an indefinite period ; I have watched larvae in 

 the same position for 45 minutes. Owing to the roots of the plant and the larvae 

 being almost alike in colour the latter are not easily recognised when attached, 

 and the plant may be readily lifted out of the water and replaced without 

 detaching the larvae, a fairly vigorous shaking being needed to induce them to 

 let go their hold. Like that of Aedomyia catasticta, the larva of Mansonioides 

 frequently feeds with the ventral side uppermost. Occurrence — June to 

 December. 



The pupae are capable of bringing their trumpets together like a pair of 

 pincers, and they also grasp the roots of the plant by means of these. They do 

 not remain below constantly like the larvae, but when once attached a vigorous 

 shaking is needed to displace them, as in the case of the larvae. 



Fig. 1. 



-Early stages of Mansonioides uniformis, Theo. ; (a) larva, dorsal view ; (&) terminal 

 segments of larva ; (c) pupa, lateral view ; (d) anal plates of pupa. 



The following is a detailed description of the larva : — 



Pearl-grey in colour, and about 4 mm. long. The head is large, but not so 

 wide as the thorax ; the antenna has a dark plume of plumose hairs about one- 

 third of its length from the base and two stout bristles at two-thirds of its 

 length ; there are two short terminal hairs and a blunt stout bristle at the apex. 

 The brushes are well developed and the face shows plumes. The thorax has 

 the usual plumose hairs. 



The siphon-tube is conical in shape, and rather more than twice as long as 

 broad ; its apical third is very dark and highly chitinised, appearing to be 

 movable on the basal portion. At the junction of the dark apical portion, on the 

 dorsal surface, are two stout curved bristles terminating in sharp points, while on 

 the ventral surface there are two dark straight hairs. A crown of hooklets 

 surrounds the orifice of the siphon-tube, those on the dorsal aspect frequently 

 having two belts. In imperfectly cleared specimens these hooklets appear to be 



