MAY FLIES AND MIDGES OF NEW YORK 273 



median and the others kiteral. The labium has rounded teeth, the 

 first laterals as long as but not as wide as the middle one; the 

 remaining laterals are more pointed. A iewed from the ventral 

 surface two oblique folds or thickenings in the chitin, one on each 

 side nearly parallel to the toothed margin, may be seen. The 

 claws of the anterior prologs are coarse and pectinate. The anal 

 prolegs and appendages resemble those shown on pi. 25, fig. 6. The 

 larvae were taken from a brook near Ithaca N. Y. 



Pupa. Yellowish; length 3 to 3.5 mm. Respiratory organs very 

 small. The marking on the dorsum of the abdominal segments (a 

 side view of one is shown in fig.15) consists of four transverse rows 

 on each of segments 2, 3, 4, and 5; and two rows on 1, 6, 7, and 8. 

 The first transverse row on a segment consists of about two or 

 three rows of extremely minute spines ; the second an interrupted 

 double row of short but stout spines; the third an irregular triple 

 row near the posterior margin ; all these pointing caudad ; and 

 finally in the fold of the incisure there is an irregular triple row 

 of much smaller ones pointing cephalad. The second and last rows 

 are wanting on segments 1, 6, 7, and 8. The caudal appendages 

 are like those shown on pl.24, fig.3, for a species of C r i c o - 

 t o p u s . Larva and pupa have recently been described by Taylor 

 (1903). 



Imago. (P1.30, fig.7) This species resembles Chironomus 

 viridis, but differs in the generic characters. Dorsum of thorax 

 with three dark brown stripes; the metathorax and sternum 

 black ; scutellum yellow ; the abdomen brownish, the forceps small, 

 the arms rather thick. Antennae, including the basal joints, 

 brown; the hairs pale brownish; palpi brownish red. Legs pale 

 yellow ; the extreme tips of the tibiae black ; the tarsi dusky ; fore 

 metatarsus one third or one fourth shorter than its tibia. Wings 

 whitish. Halteres yellow. Length 2.75 to 4 mm. Greenland, New 

 York, Washington, Texas, Illinois. 



Zetterstedt's description of variabilis, which is considered 

 a synonym of the above, is as follows : 



Male. Antennae with dark hairs. Head blackish ; palpi fus- 

 cous. Thorax subopaque. yellow or testaceous, with three black or 

 brown stripes, often distinct, sometimes very wide subconfluent, 

 covering nearly the whole of the dorsum, leaving the humeri pale. 

 Sternum blackish; scutellum more or less yellow; metathorax 

 black. Abdomen narrow, hairy, black, the venter yelloAvish or 

 testaceous, after death often blackish. The caudal end black, the 

 appendages leaf -like or narrow ovate. Wings white or cinereous 

 hyaline, spotless; halteres pale yellow. Legs nearly bare, brown, 

 fuscous or testaceous, the femur toward the tip often darker, the 

 fore coxae yellow, the tarsi often fuscous, especially the fore pair. 



