PUPAL STAGES OF WEST AFRICAN CULICID.E. 35 



liairs, but the long hairs on the other segments are only siibplumose. All 

 the other hah's on the segments are short and simple, including a number o£ 

 the minute stellate form. The sub-siphonal plumes are moderate in size and 

 are o£ plumose hairs, the pubescence being rather thick, though short ; the 

 siphonal plumes are small, and the anal plumes nre also shortly plumose. 

 The comb is very difficult to see ; under favourable conditions it appears 

 iis an anterior row of about sixteen subobloug scales, and a posterior one 

 -of six. 



The siphon is about half as long as the abdomen, stout but tapering, more 

 than four times as long as its base, the end is light in colour for about 

 1- of the length ; this is followed b}^ a dark ring which gradually becomes 

 lighter to the base, where the usual chitinous ring is present ; this character 

 is very marked in five out of six larvae, and in the sixth it is fairly obvious 

 (PI. V, fig. 2). The spines do not begin till a short way from the base : three 

 to five are present, being rathei- small, and running for less than one-third of 

 the length ; they are followed by two long subplumose hairs (four, counting 

 both rows), and in the dark ring is sometimes a single lateral hair and a short 

 triple or double one — these appear variable ; the valves at the much tapered 

 end are small, and have a few bent short hairs on them ; the contained tracheae 

 iire large, as is usually the case. 



The anal segment is short, as long as broad (it widens posteriorly), with 

 stout papilla? of slightly unequal length; the longer nearly twice the length 

 of the segment ; they have a spotted appearance, though fairly hyaline. 

 There are four long strong hairs on the dorsal edge ; the ventral beard is 

 small, not longer than the smaller papillae, and mostly at the distal end. 



Larva 4J mm. long, siphon 11 mm. 



Pupa. 



The pupae are variable in colour, as one is quite dark, and the other quite 

 light, and they are rather characterless ; the plumes on the seventh segment 

 are short but thick and of subplumose hairs ; in the same place on the sixth 

 segment is a triple hair. In this case the dark form is easily seen to be that 

 of the mature pupa, as the rather large scales on the abdomen of the imago 

 ■C'.n be seen when the pupa is examined from the dorsal side (PL Y, fig. -i). 



Length of thorax 1^ mm. 



Described from six larvae and two pupae. 



[Larvae found in a tub of dirty water in July. The larvae are very 

 common in barrels, tubs and ponds in June, July and August. The egg- 

 raft is 4 to 6 mm. long, formed of 170 to 250 bottle-shaped eggs disposed in 

 4 to 9 rows. The eggs are laid between sunset and dawn, and hatch in about 

 24: hours.— W. M. G.] 



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