220 NEW YORK STATE MUSEUM 



(fig,6). Upon the liyi;oi)liarviix (hj) is a pair of slender branched 

 processes besides the usual hairs and papillae. The middle pair 

 of the teeth in labium (fiji.') Ij are the longest, and the second,, 

 third and fifth laterals are longer than the first, fourth and 

 sixth. The setae of the anterior prologs are jtale brown, and 

 rather coarser and more distinct than those of most of the 

 Chironomid larvae (fig.8). The posterior prolegs have the 

 usual bilobed claws of which the two lobes of each marginal claw 

 make a smaller angle with each other than do the central claws 

 (fig.9). Immediately dorsad of the four short and thick anal 

 blood gills is a pair of small setae; the basal nodule upon which 

 each dorso-anal tuft of setae is placed is quite small, about as Avide 

 as it is long. The ventral blood gills of the eleventh abdominal 

 segment were not seen in this specimen. 



Pupa. (Figs. 11 and 12.) The pupa is gTeenish brown, about 

 G mm. in length, with the usual pair of white thoracic respiratory 

 tufts. The dorsum of the second and third abdominal segments 

 are marked as shown in fig.ll. Near the anterior margin of each 

 of segments four, five and six is a transverse row of short but 

 conspicuous dark spines. The epidermis at the base of each spine 

 is brown ; the entire dorsal surface of the segment behind this 

 row is microscopically punctate with extremely short spines. 

 Near the posterioi' margin these spines become somewhat larger, 

 forming an irregular double or triple transverse row. Second 

 segment is like the following segments, but has in addition the 

 usual transverse row of longitudinal ridges on its posterior mar- 

 gin. All these segments have a few pale setae arranged as shown 

 in the figure. The seventh and eighth segments are nearly devoid 

 of markings, though they have a few small setae. The lateral fins 

 of the eighth segment each has the usual lateral filaments, and 

 each ends in a chitinous comb of five teeth (fig.l2). The caudal 

 fin has the usual fringe of matted hairs. 



Imago. (P1.28, fig.15.) Male and female, blackish; legs white, 

 male with Avhitish abdomen. Length 4 to 5 mm. 



Male. Head, including paljii, ])roboscis, antennae and its hairs 

 pale fuscous. Dorsum of the thorax dark brown with three sub- 

 shining broad blackish stripes, metanotum and pectus blackish; 

 I)leura and scutellum a little paler. The hairs of the mesothorax 

 and scutellum yellow. Abdomen white Avith a greenish tinge, the 

 last three joints including the genitalia sometimes pale fuscous, 

 and occasionally the posterior margins of segments very narrowly 

 darkened. The claspers elongate, the inferior lobes slender and 

 slightly clubbed. Hairs pale. Legs white, the tips of the middle 

 and hind tibiae each with a minute black circular comb with two 

 of its teeth slightly elongated into spurs. Fore tarsi of male, 



