126 



seta, a short one and a small digit. Anteantennal tuft, lower and upper frontal tuft 

 all multiple, number of hairs in the two last-named tufts generally five and gener- 

 ally inserted over each other, the six tufts commonly not lying in an arcuated line; 

 two small single hairs, between upper frontal tufts. Eyes rather large. Thorax round- 

 ed, wider than long. Hair formula of frontal border 221123321122. Hairs in 3 very 

 long, reaching far beyond the brushes when extended; lateral hairs single and in tufts. 

 Anterior abdominal segments short, posterior ones elongated; lateral tufts of 

 first two segments multiple, two hairs on third to sixth. Subdorsal hairs in the 

 domesticated races double on third to sixth segment. Airtube very long, about five 

 times longer than wide ; pecten consisting of about ten teeth, short, only on basal 

 third, single tooth oblique, triangular, feather-like, with from five to seven branches. 

 Hair-tuft of air-tube with four or five hairs. Between the hair-tuft and apex four 

 tufts double, the one of them out of line. Comb of eighth segment consisting of 

 numerous scales in a triangular patch, the single scale with feathered tip; hairs of 

 eighth segment in common arrangement. Anal segment a little longer than broad, 

 ringed by a plate. Dorsal hair-tuft feebly developed, consisting only of from six to 

 seven unequally long hairs; a single lateral hair; ventral brush well-developed, con- 

 fined to the barred area, without free tufts before it. The brush consists of about 

 10 — 12 rays, every ray carrying about five to seven hairs. 



Lateral tufts of the labelium very large distinctly divided in two parts, but 

 the inner part without comb-bristles; palatum covered with rather short hairs. 

 Mandible quadrangular, three stout spines before the collar and some short hairs 

 arising from their base; a row of long cilia from a collar; outer margin with about 

 ten scales bearing short hair-tufts. Dentition: three teeth on a process, the first of 

 them very large; a long serrated tooth before; process below undivided with a few 

 hairs; angle below sharp; a group of hairs within and a row at base. Maxilla high, 

 conical, divided by a suture. At the apex a tuft of very long, feathered hairs; along 

 the suture a series of shortening hairs. Inner half between suture and inner margin 

 with sharply defined series of long soft hairs; inner margin itself furnished with a 

 series of long stiff bristles; the outer half with a spot covered with soft hairs 

 and a short spine near apex. Palpe moderate, four terminal digits rather long. 

 Mental plate high with straight sides and triangular apex; a large central tooth 

 and from nine to eleven teeth on each side; the first three small and densely crow- 

 ded. Colour commonly greyish-brown, often almost milky-white. 



Biology. Of all our European mosquitoes, this is the most domesticated spe- 

 cies. In some regards it is the best studied; it is on this mosquito, that Beaumur 

 has written his classical memoir and its life-history has been used as a model of 

 all other European mosquitoes. Its anatomy is better studied than is the case with 

 most of the other mosquitoes. I refer more especially to the papers on the genital 

 organs by Lomen (1904 p. 567); Heimann (1913 p. 1); Kulagin (1901 p. 578); Kopf- 

 bau (Kulagin 1905 p- 285 ). Of course we know the developmental stage for this 

 mosquito better than for all other larvae; if however we will try to describe 



