262 AGRICULTURAL EXPERIMENT STATION. 



Habits of the Adult. 



No observations have been made by any member of the force 

 upon this species which wiU be ahnost certainly found along the 

 shores of the Delaware River in Warren County and probably of 

 some other streams in the rocky section of the State. 



Dr. Harrison G. Dyar, who has published the life history from 

 observations made in New Hampshire and along- the banks of 

 the Potomac, says that the adults are ver)- troublesome on and 

 about the river and bite freely. 



Description of the Larva. 



The larva with structural details is illustrated on plate figure 

 80. When full grown it is 7-9 mm.,^.28-.36 of an inch in 

 length and of a pale grayish wdiite color except the head, siphon 

 and ninth segment. The head is rounded, almost as broad as 

 long, blackish brown, with four rather short hairs arising from 

 separate points in the anterior part of the vertex ; a small hair 

 tuft composed of four or five hairs is at the base of each antenna. 

 The antenna (fig. 80, 3) is rather short, almost as broad at the 

 tip as at the base, uniformly dark brown in color and sparsely 

 set w^ith small spines ; the apex has one long spine, three smaller 

 ones and the usual small peg. The hair tuft issues from the shaft 

 slightly below the middle and consists of but two fine hairs, which 

 do not reach the apex. The eyes occupy the part where the head 

 is widest and are very small, consisting of a crescent shaped piece 

 and a very small detached portion in the concavity. The whole 

 is surrounded by a small ring of yellowish white, strongly in con- 

 trast with the dark colored head. The rotary mouth brushes 

 (fig. 80, 4) are yellowish brown wath the more central hairs 

 pectinated at their tips. The mandible ffig. 80, 2) is normal but 

 rather broad. The maxillary palpus (fig. 80, 6) tapers toward 

 the apex, and has a moderate apical tuft and medium-sized, 

 stout, basal joint. The mentum (fig. 80, O is broadly triangular, 

 almost three times as broad at the base as long and with nine or 

 ten teeth on each side, small at the apex, becoming larger toward 

 the base. 



The thorax is a little larger than the head, rounded and with 

 slight angles at the sides, each angle giving rise to rather long 

 hair tufts. 



The abdominal segments from one t*^ seven are greatly elong- 

 ated, very disproportionate to the small thorax and comparatively 

 large head; the lateral tufts have each three to five hairs, dimin- 



