MOSQUITOS OF THE PALAE ARCTIC REGION. 309 



curved. Palpi rather long, nearly one-third as long as the proboscis. Wings rather 

 scantily scaled (not rubbed) ; veins all pale, membrane whitish ; costal scales all 

 whitish-yellow ; first longitudinal vein with some dark scales. Integument of legs 

 pale yellow, scales almost all whitish-yellow, those on the terminal tarsal segments 

 browner ; no sign of pale tarsal rings. Claws all toothed. Integument of thorax 

 and abdomen blackish. 



W. Siberia : Omsk (Grand) ; 1 $. Type in Helsingfors Museum. 



15. Aedes (Ochlerotatus) alpinus (Linn.). 



Culex alpinus, Linnaeus, Flora Lapp. Ed. 2, p. 381 (1792). 



Ctilex nigripcs, Zetterstedt, Ins. Lapp. p. 807 (1838) ; Henriksen and Lundbeck, 



Med. ^Groenland, xxii, p. 595 (1917). 

 Aedes innnitus, Dyar and Knab, Insecutor Inscitiae, v, p. 166 (1917). 

 Aedes {Ochlerotatus) ncarcticus, Dyar, Rept. Canad. Arctic Exp. iii, Pt. C, p. 32 



(1919). 

 Aedes alpinus, Dyar, Insecutor Inscitiae, viii, p. 52 (1920). 



This species is fairly readily distinguishable by the unusually dense bristles on 

 the thorax, looking, as Dyar has remarked, " as though it had a long woolly coat 

 to keep out the cold." The very dark colour of the mesonotal scales, the black 

 integument of the whole bod}^ and the straight, shining greyish-white abdominal 

 bands are also characteristic. ' However, since the density of the bristles is some- 

 what variable (smaller specimens being less bristly), and they are also rather liable 

 to denudation (though less so than the scales), it is not always easy to distinguish 

 the species from A. cataphylla and A. parvidus. In fact A. alpinus might almost 

 be regarded as a race of A. cataphylla which has become adapted to arctic conditions 

 by the multiplication of its bristles and the thickening of the chitin of the 

 whole body. 



I have failed to obtain a European male for examination from any correspondent, 

 and it is very unfortunate that the good series of the species brought from north 

 Russia by Capt. Garment and Dr. E. A. Cockayne consisted of females only. I 

 am, however, indebted to Prof. Sj5stedt and Dr. Lundbeck for several males from 

 south-west Greenland. These differ ixom the females (from the same place) in 

 showing hardly any scales on the thorax ; consequently they appear a good deal 

 blacker ; they are also even more hairy, especially on the abdomen. The hypopygium 

 very much resembles that of A . cataphylla, except in being far more heavily chitinised, 

 especially in the anal and genital pai'ts. The apical lobe of the side-piece is very 

 small, hardly distinguishable ; the basal lobe has a moderately stout spine. 



It seemed highly probable that these Greenland specimens were A. innuiius. 

 D. & K., but that species was described. as having a " double angular membrane " 

 on the appendage of the claspette, as in A . lazarensis, while the males I have examined 

 showed the normal single membrane. Dr. Dyar therefore re-examined the types 

 of A. innuiius, and reports that the original description was in error ; the membrane 

 is really single, and the structure of the hypopygium of A. innnitus and A. nearcticus 

 is really identical. That being so, there can be little doubt that A. alpinus is also 

 the same, especially since we now know that a number of northern species of Aedes 

 are common to the Old and New Worlds. 



Distnbution.—VrohsiUy a circumpolar species, occurring in all the lands to 

 the north of the Arctic Circle. I have seen males and females from south-west 

 Greenland, and females from Finmark, Lappland, Murmansk, and north-west 

 Siberia ; also a female from the Paris Museum labelled " Fontainebleau, Dufour et 

 Laboulbene." In regard to this last there must surely have been some mistake in 

 labelling. 



