368 NEW YORK STAT35 MUSEUM 



none on joint 3; anterior margin of joint 9, and of subjoint with 

 a continuous row of smaller, anteriorly curved hooks; joints 7 

 and 8 unarmed dorsally; ventrally joints 6, 7 and 8 have each 

 four minor hooks. 



Cocoon. Length 3.5mm. Neater than that of any other spe- 

 cies known to me, being formed of fine threads, lined with gel- 

 atinous ones. The web is quite dense, uniform, with well de- 

 fined, sometimes thickened ribs. The cocoon is always securely 

 fastened singly to leaf or stick, and if many are fastened on 

 the same leaf, they do not crowd each other. It fits snugly 

 about the pupa, which is so securely anchored inside as to be 

 with difficulty extricated. 



Several female specimens taken by Messrs MacGrillivray and 

 Houghton at Axton N. Y. in company with S. vittatum 

 agree perfectly with Poquillett's description, though not so well 

 with Riley's. Coquillett's description of the female in United 

 States Dep't Agric. bulletin 10, new series, reads as follows: 



Abdomen of female gray, marked with a velvet-black fascia 

 on segments 3 and 4, and sometimes with two subdorsal spots 

 of the same color on 2, 5 and 6; thorax bluish gray with three 

 black vittae. 



The blue color on the abdomen spoken of by Riley in his de- 

 scription is not distinguishable in the dried cotype specimen, 

 the posterior segments appearing grayish. In the male the 

 thorax is velvety black, with a few pale yellow hairs, specially 

 anteriorly and posteriorly. The abdomen is velvet-black, the 

 posterior margins of segments sometimes pale. The fore tibia 

 possesses a single spur, the middle and hind ones each with a 

 pair [pl.38, fig.l2]. All tarsal claws ol the male trifid [pl.38, 

 flg.18] ; of the female bifid [pl.38, fig.l6]. 



It may be mentioned that what Riley calls mentum I have 

 termed labium. To Riley's description of the larvae may be 

 added that the apical pair of bristles of the mandible is not 

 present or at least is not differentiated from the other hairs; 

 the labrum and hypopharynx [pi. 33, fig.ll, 3] resemble those 

 of other species; the labium has four pairs of setae [pl.33, flg.4:], 

 one of which is quite small; the maxillary palpus has no setae 

 on the last joint, and but few hairs on the basal joint. No 

 spines are apparent at tip of the last abdominal joint of pupae, 



