MOSQUITO BIOLOGY 201 



quote: "I first noted the larva in an open sewage drain of the college 

 campus in 1901. They attracted my attention by their large size as 

 compared with the larvae in C. fatigans, which were so numerous in 

 the same drain. At this time several adults were taken from the weeds 

 and grasses overhanging the ditch. ... In the summer of 1903, I 

 noted scores of large larvae in a roadside pool near Starkville, Mis- 

 sissippi. At first sight they appeared to be the larvae of Anopheles, for 

 apparently they were in horizontal positions. Never having seen Anoph- 

 eles larvae so abundant, it seemed worth while to stop and examine 

 them in some detail. Much to my astonishment these larvae were found 

 to be members of the genus Culex, or at least of some genus closely 

 related to Culex. Moreover, the great majority of them were lying 

 apparently horizontal, just below the surface film of water. . . . 

 From this time forth many larvae of this species were found in other 

 rain water pools and abundant opportunity was afforded to observe 

 them. With the one exception of those found in the sewage ditch, I 

 have always found these larvae in transient rain water pools. 



"The larvae are interesting from the position they assume in the 

 water. When the larva rises to the surface it assumes at first about the 

 same position as the larva of Culex. But after a moment, if left undis- 

 turbed, the body, with a slight jerk, floats quickly to an approximately 

 horizontal position with the head on a level with the surface of the 

 water, in which position the mouth brushes are able to skim the surface. 

 The larva can change quickly and easily from the horizontal to the 

 suspended position. The body, instead of lying nearly horizontal as 

 does that of Anopheles, hangs suspended — like a piece of slack rope 

 — between the head and respiratory tube and considerably below the 

 surface of the water. The respiratory tube projects out of the water at 

 least a third of its length and points forward when the larva assumes 

 the horizontal position. . . . The larvae are splendid swimmers and 

 are constantly swimming along the surface, but nearly always in a 

 backward direction. 



"Mr. Theobald states that the eggs, as noted by Dr. Grabham are 

 laid singly. Although careful search for the eggs was repeatedly made, 

 they could not be found. The larvae would invariably appear in a pool 

 within twelve hours after the formation of the pool by a rain storm. 

 The conviction was gradually forced upon me that the eggs were 

 deposited in or upon the mud to await the coming of the rain." 



In a general way our observations agree with those of Professor 

 Herrick ; but in New Jersey the habit of assuming the horizontal posi- 

 tion seems much less developed. The younger larvae do assume and for 



