226 AGRICULTURAL EXPERIMENT STATION. 



and numerous small ones scattered on the basal half. The tuft 

 of four or five hairs is situated at the middle, and does not reach 

 the tip of the antenna, which has the apex terminated with one 

 long and one short spine, two short bristles and a small articu- 

 lated peg. The eyes are of moderate size, semi-circular in out- 

 line, with a small detached portion at the posterior edge. The 

 rotary mouth brushes (fig. 66, 2) are thick, composed of hairs 

 which in the more central portion are pectinated. The mentum 

 (fig. 66, 4) is triangular in form, about as long as broad and 

 with slightly curved series of from twelve to fourteen small teeth 

 on each side of the apex. The mandible (fig. 66, 3) is normal, 

 set with small spines at its base. The maxillary palpus (fig. 

 66, 6) is short and very broad, with hairs and spines arranged in 

 patches on the surface and with a comparatively small apical, 

 tuft; the basal joint is rather large, with small, stout spines at 

 its apex. The thorax is rounded, with rather short hair tufts 

 issuing from slight angles at the sides. The anterior margin 

 also, with two short hair tufts. The abdomen is long, the ante- 

 rior two segments transversely oblong and with lateral tufts of 

 four or five hairs ; the central and posterior ones lengthened 

 and narrower, with only two hairs to the lateral tuft up to seg- 

 ment seven. The eighth segment has lateral patches of from 

 twenty-eight to thirty-four scales, without an}^ regular arrange- 

 ment ; the single scale (fig. 66, 8) has spines at the apex and 

 along the sides, the apical one largest and longest, the 

 other diminishing in size toward the base. The anal siphon 

 (fig. 66, 7) is about four times as long as its width at 

 the base and has two series of toothed spines, each 

 ranging from seventeen to twenty-two in number. The spines 

 are black, white tipped, with the teeth not quite reaching the 

 middle; a common arrangement is for four teeth to form two 

 pairs, as shown in one of the figures. The ninth segment is 

 longer than wide, with the two dorsal tufts and the ventral row 

 of tufts present, as usual. The tracheal gills are only slightly 

 lonsfer than the ninth segment. 



^fe^ 



Habits of the Early Stages. 



Full grown larvae were found by Mr. Grossbeck, April, 1903, 

 near Paterson, with canadensis. The larvse were recognized as 

 distinct, but were not bred. April 25th, Mr. Van Duersen 

 brought in four well grown larvje from swampy woods near 

 New Brunswick; but these also failed to develop. May 2d, 

 another lot of mixed larvse was brought in. mostly canadensis. 



