NOTES ON CULICIDAE. 217 



Left maxilla normal ; right present, but abnormally slender. Left front claws male, 

 right female ; left middle claws female, right male. Genitalia male, perfectly normal. 



Specimen 5.— Left antenna with basal joint as in female ; next 10 joints very short 

 and with long hairs, but not truly male in character ; last three joints more elongate 

 and female in appearance. Right antenna similar, but much less hairy, and the last 

 7 joints almost typically female. Left palp about a third as long as the proboscis, 

 the terminal joint much larger than in the female, oval, but not very hairy. Right 

 palp similar, but a little shorter. Hypopharynx, mandibles and maxillae normal 

 (female). Inner left front claw longer than outer, but without a tooth ; right front 

 claws female. Inner left middle claw longer than outer, but shorter and straighter 

 than in male ; right middle claws normal (female). Genitalia female, quite normal. 



Specimen C. — Left antenna similar to that of specimen B, but the ante-penultimate 

 joint is shorter. Right antenna similar to the left. Left palp similar to that of 

 specimen B. Right palp a little longer and more hairy than the left. Hypopharynx, 

 mandibles and maxillae normal (female). Front claws female. Inner claws on 

 mid legs a little longer than the outer, that on the left leg without a tooth. Genitalia 

 normal, female. 



Ochlerotatus dorsalis, Mg., and 0. salinus, Fie. (fig. 6 a, b). 



So far as I am aware, the larvae of these two species have never been described. 

 They are usually found together, the larvae feeding in brackish or salt water. I found 

 larvae at Beckton Marsh, London, E., in April 1914, and at Tal-y-bont, Merioneth, 

 in July 1914. In the latter case the young larvae were in a rather foul puddle 

 of brackish water immediately behind a shingle bank ; the larval and pupal stages 

 occupied about a fortnight, so that there are evidently several generations in the 

 year. 



The larvae of both these species rather closely resemble those of 0. nemorosus, but 

 are easily distinguishable under a microscope. The following characters will serve 

 to distinguish the three species. 



0. nemorosus : Antennae not conspicuously lighter at the base. About 12-16 

 scales in the comb of the eighth segment ; scales slightly fringed at the base and 

 produced into very long sharp points (fig. 6 a). Teeth of pecten with two or three 

 serrations near the base, of which the apical one is much the largest. Gills a little 

 longer than the anal segment, sharply pointed. 



0. dorsalis : Antennae conspicuously pale at the base. About 24 scales in the 

 comb of the eighth segment ; scales pointed, but shorter than those of 0. nemorosus 

 and heavily fringed (fig. 6 6). Teeth of pecten with two or three serrations near 

 the base, of which the apical one is considerably the largest. Gills scarcely half as 

 long as the anal segment, bluntly pointed. 



0. salinus : Antennae conspicuously pale at the base. About 24 scales in the 

 comb of the eighth segment ; scales blunt-ended, heavily fringed (fig. 6 c). Teeth 

 of pecten with three or four serrations near the base, of which the apical one is very 

 httle larger than the others. Gills very short, almost globular, the dorsal pair a little 

 longer than broad. 



It is very interesting to note that 0. salinus, which in the adult is so much like 

 0. mmorosus, differs more in the larval stage from 0. nemorosus than 0. dorsalis does. 

 (C325) B 



