212 ¥. \V. EDWARDS. 



Ochlerotatus (F.) geniculatus, 01. 



The early stages of this species have never been described, nor is there any certain 

 record of its breeding habits, though ( Jalli-Valerio and Rochaz de Jongh,* in recording 

 that they have found larvae of C. ornatus in holes at the bases of trees, are very 

 probably referring to 0. genicidatvs. 



Early in April of the present year (1916) I found large numbers of larvae, in company 

 with those of Anopheles pluinheus, in holes in beech trees at Burnham Beeches, Bucks. 

 The larva is peculiar in several respects, having a greater resemblance to those of 

 Slec/omi/ia than to those of Oelthrolatiis. The following description should make it 

 easily recognisable : — 



Antennae rather long, almost straight, slightly tapering towards the tip ; a single 

 hair in place of a tuft about the middle ; no trace of minute spines over the surface. 

 Frontal hairs : the usual four pairs present, two large and two smaller ; of the two 

 larger pairs the anterior is two-branched, the posterior simple, almost in a line 

 longitudinally with the an'l^erior pair ; both these only about as long as the antennae ; 

 the median pair small, four- or five-branched above the base, rather close to and almost 

 in a line transversely with the anterior (two-branched) hair. Much further back, near 

 the edge of the cl}-peus, is an additional single hair. Abdomen with numerous rather 

 long four- or five-branched '' stellate " hairs scattered over both the dorsal and 

 ventral surfaces. Comb of eighth segment with about 12 teeth in a single, regular, 

 slightly arched row ; the teeth apparently simple and produced into long sharp points. 

 Siphon about three times as long as its base, regularly narrowed towards the apex ; 

 pecten with 14-17 teeth, all close together, in a slightly diagonal row extending onfy 

 about a (juarter of the length of the siphon ; the first three or four teeth short, the 

 rest much longer, each with one or two minute serrations at the base. Tuft of four 

 simple hairs, in a line with the apex of the pecten, placed before the middle of the 

 siphon. Anal segment with a chitinous saddle, the posterior edge of which is minutely 

 spiny and carries a long three-branched hair. None of the hairs on the anal segment, 

 or indeed anywhere on the body, are plumose. Upper pair of gills a little longer than 

 the anal segment, and about half as long again as the lower. 



Larvae of all sizes from newly hatched to full-grown, but mostly quite small, were 

 found in the tree-holes on 4th April ; the first adult did not hatch out till 22nd April, 

 but some of those which were only in the first or second stage on 4th* April had pro- 

 duced adults by 4th May. 



The adult is a very vicious and persistent biter. 



Young larvae of a second brood were found in a hole at the base of a beech-tree in 

 Cassiobury Park, Watford, on 21st August. 



Ochlerotatus (F.) koreicus, sp. nov. 



Head with a broad patch of narrow white scales on the vertex ; on each side of this 

 a roundish area of broader black scales ; scales at the sides fiat, white, including a 

 black spot ; narrow white scales round the upper part of the eye-margins. Clypeus 

 bare, black. First antennal joint with small flat white scales. Palpi and proboscis 



* See KevieAV of Applied Entomology, i, 1013. p. 40. I hive been u.iiible to consult 

 the original paper. 



