AEDE8 TRICHUEUS 759 



AEDES TRICHURUS (Dyar) Dyar & Knab. 



Oulex punctor Dyar (In part, not Klrby), Proo. Ent. Soe. Wash., vl, 39, 1904. 



Oulex impiger (no. 2) Dyar & Knab (not Walker), Proc. Ent. Soo. Wash., vi, 144, 1904. 



Culex trichurus Dyar, Journ. N. Y. Ent. Soc, xii, 170, 244, 1904. 



Culex cinereoborealis Pelt & Young, Science, n. s., xx, 312, 1904. 



Culex clnereoborealis Pelt, Bull. 79, N. Y. State Mus., 312, 1904. 



OuUcada cinereoborealis Felt, Bull. 79, N. Y. State Mus., 3916, 1904. 



Culex trichurus Dyar, Journ. N. Y. Ent. Soc, xlii, 109, 1905. 



Culicada trichurus Pelt, Bull. 97, N. Y. State Mus., 447, 478, 1905. 



Orabhamia trichurus Dyar, Proc. Ent. Soc. Wash., vll, 48, 1905. 



Aedes trichurus Dyar & Knab, Journ. N. Y. Ent. Soc, xlv, 191, 1906. 



Ochlerotatus cinereoborealis CoquUlett, U. S. Dept. Agr., Bur. Ent., Tech. Ser. 11, 



18, 20, 1906. 

 Ochlerotatus trichurus Dyar, U. S. Dept. Agr., Bur. Ent., Clrc. 72, 4, 1906. 

 Culicada trichura Theobald, Mon. Culic, iv, 357, 1907. 

 Culicada cinereoborealis Theobald, Mon. Culic, Iv, 367, 1907. 

 Culicada trichura Theobald, Mon. Culic, v, 305, 1910. 

 Culicada cinereoborealis Theobald, Mon. Culic, v, 307, 1910. 



Obioinai, Description op Cttlex tkichtibus : 



Culex punctor Kirby, Is one of those single-brooded, early developing mosquitoes 

 that would seem especially adapted to an arctic climate. Three-fourths of the year 

 is spent in the egg state. The eggs, lying in marshy places frozen up over winter, 

 hatch as soon as the ice has melted In the spring. The larval stages are passed In 

 about three weeks, even in very cold water and the adults emerge immediately. 

 They may fly possibly for six weeks, when the eggs being laid, they die and the 

 species disappears, apparently, for the season. With these habits the insect ought 

 to occur throughout the arctic circle. I met with It in Canada in the mountains of 

 eastern British Columbia (Proc. Ent. Soc. Wash., vl, 39, 1904). A single fully grown 

 larva, apparently the last one of a brood, was found on May 31. It soon pupated and 

 the imago occurred on June 4. Other mosquitoes were flying at this time over the 

 swamp where the larva was found and were supposed to be of the same species. On 

 being Imprisoned, they were fed on sugar and water. After being In confinement for 

 two weeks, a female deposited eggs on the surface of the water. They were kept in 

 water all the summer and following winter and hatched as soon as the ice melted 

 the following spring. The eggs were laid singly. They are peculiar, being very wide 

 and angularly shaped. They float at first, but soon sink or become adherent to 

 objects at the side of the pool or floating on it. 



On rearing the eggs that had hibernated, I was surprised to find that the larvae 

 differed markedly from punctor and were obviously a distinct species, the Imagoes 

 of which I had confounded with punctor, I have referred to the egg as that of 

 punctor (Proc. Ent. Soc Wash., VI, 39, 1904); this reference should be cancelled. 

 The mature form I have In only very slender material. The original female' from 

 which the eggs were obtained Is badly rubbed and a male bred by Dr. Dlmmock at 

 Springfield, Mass., from an identical larva. Is broken. Mr. CoquUlett has kindly 

 examined the specimens and does not detect any difference; but he considers the 

 material too poor to form an opinion on. I am inclined to designate this form 

 provisionally as Culex trichurus. In order that It may be referred to. The name Is 

 given in allusion to the unusually hairy air tube of the larva, since It Is the only 

 species of the short-tubed group that has more than a single hair tuft. 



Early Stages of Culex tbichtjeus Dyab. 



Egg. — Thickly fusiform, the ends well tapered, one side more bulging than the 

 other. Black, the surface very finely granular shagreened all over, no sculpturing, 

 no mucilage. Laid loosely, floating, but sinking at the first touch or adhering by 

 surface tension to marginal objects. Length 0.6 mm., width 0.3 mm. 



Stage I. — Head rounded, fiattened, normal; antennas moderate, equal, with small 

 spinules, terminal digits and tuft of hair at the middle of the joint, all darkly In- 

 fuscated. Body moderate, equal, submonlliform, normal; hairs moderate, becoming 

 gradually less posteriorly. Air tube moderate, about three times as long as wide, 

 the basal two thirds colorless, the tip Infuscated; pecten of two rows of flat, dentate 

 plates with long marginal spine, the single hair arising well within the pecten and 

 nearly at the middle of the tube. Lateral comb of the eighth abdominal segment a 

 row of obscurely digltately spined teeth with central longer spine in a single row, 

 parallel, approximate, six, seven or eight In number. Anal segment with a small, 

 rounded quadrate dorsal plate, darkly Infuscated; terminal hairs and four anal 

 processes normal; no ventral brush. The body is pigmented in brown over the dorsal 

 region. 



