86 



tufts on segments one and two multiple, on segments three to six double; a pair 

 of subdorsal hairs on segments one to six, largest on segments four to six. Hairs 

 of segment eight in normal arrangement. Lateral comb consisting of about 15 scales, 

 triangularly arranged in two irregular rows; each scale with a broad spatulate base 

 and a very strong median thorn, two shorter lateral thorns and many shorter ones 

 bordering the spatulated part. Sipho straight, a little more than three times longer 

 than wide; pecten at basal third highly developed, consisting of about fifteen to twenty 

 strong dark spines, the first of them without lateral thorns, the others with one or two. 

 The pecten reaches to the hair-tuft; between it and apex two or three strong spi- 

 nes with large distance between each other; dorsal to the pecten and about half- 

 way along it a small hair. On the opposite side of the sipho four pairs of hair- 

 tufts, more or less conspicuosly double, arranged in two lines. Anal segment much 

 longer than wide, almost covered by the dorsal plate. Dorsal tuft well-developed 

 with two very long, stiff hairs. Ventral brush in the barred area consisting of nine 

 rays each with from six to eight hairs; before barred area three or four free tufts. 

 Anal gills very short, broad, almost equal. 



Lateral tufts of labrum short, a crown of comb-bristles nearest to the pala- 

 tum which is covered with long, soft hairs. Mandibles quadrangular, four stout spines 

 before collar, a row of long cilia from a collar; about ten spines from margin; 

 dentition very strong: four teeth, the first of them strongest, between them and the 

 marginal spines two strong spines; below the teeth a series of bristles. Process 

 below but slightly furcate, with strong hairs at apex; a group of hairs at base. 

 Maxilla* of very remarkable form, almost wider than long, divided by a suture 

 with a large hair-tuft on the broad, oblique apex and a spine near it; coating of 

 soft hairs on both sides of suture; longest on the inner surface; no spines at inner 

 margin; palpe high, almost as high as maxilla; at the apex live conical digits. 

 Mentum broad, triangular with curved sides; a median tooth and 10 — 12 rather 

 large teeth on each side. Colour greyish, dark, often almost black with yellow head. 



The species has been described by Theobald from England (1901 p. 73) and 

 refound by Edwards (1912 p. 219). It has also been found by Goethgebour (1910 

 p. 84) hi Belgium and by Eckstein at Strassbourg (1910 p. 67). The larva has been 

 shortly described by Eckstein (1919 p. 293). The species is new to our fauna. In 

 accordance with my observation Goethgebour remarks que "l'espece est la plus 

 precose dans nos environs. Je n'ai plus revu l'espece a partir de la mi-juin". 



Biology. In November — December 1918 I found, in two ponds near Hillerod, 

 together with C. morsitans a huge, fullgrown, almost black mosquito-larva which I 

 immediately saw must give a species hitherto unknown to me; in the ponds 

 the larvae were always rare; and that year I found them only in the two above- 

 named ponds, lying near each other in the forest at the mainroad between Copen- 

 hagen and Hillerod. Though the ponds were only about two hundred yards in cir- 

 cuit and were only a few decim. deep, and though I used my net for about an 

 hour, I could only get a few larva. In December the ponds were frozen over, but 



