AQUATIC INSECTS IX NEW YORK STATE 397 



two short spines. Tlie thorax is cylindrical, of jireater diameter 

 than the abdomen; the two black air sacs distinctly visible. 

 The abdomen is of circular cross section, tapering gradually 

 toward the caudal end. Segments are subequal in length ex- 

 cept the first, which is somewhat shorter; each provided with a 

 few short hair tufts. The black air sacs of the seventh seg- 

 ment are large and distinct. On the ventral surface of the anal 

 segment [fig.O] is a fan of 25 long, feathered hairs, arranged 

 on a keel or ridge. At the apex of this segment are four elon- 

 gate blood gills and four long, feathered hairs, and near the 

 apex, arranged in a transverse row on each side, is a comb 

 of about 15 small, short hooks, curved cephalad; attached 

 to the base of each hook is a delicate transparent, sickle- 

 shaped blade, with a serrate inner margin; the surface of the 

 blade is covered with transverse ridges, which give it the appear- 

 ance of a curved pectinate hair, owing to its transparency. 

 The combs are difficult to see. Ventrad of the combs is a pair 

 of large blunt hooks curved cephalad. 



The pupa [flg.2] resembles that of Culex, pale yellow in color, 

 the thorax with three brown longitudinal stripes, the middle 

 one divided by a yellow line. Eight abdominal segments are 

 present, the first and eighth shorter than the others, and on 

 each are found a few scattered hairs. Attached to the eighth 

 segment are the swimming paddles [fig.5] ; these ditfer from 

 those of Culex in having, besides the median rib, each margin 

 also supported by a rib. On the inner rib is a row of cilia. 

 The breathing trumpet [fig.20] is spindle-shai^ed, covered with 

 a close network of pentagonal and hexagonal figures. The small 

 aperture is at the apex. 



Corethra punctipennis Say 



Acad. Nat. Sei. Thila. Jour. 1S23. 3:10. and Compl. Wr. 2:43. Wiedemann. 



1S28. 1:14 



Whitish; wings and feet punctured with fuscous. Inhabits 



Pennsylvania. 



Hair of the antennae yellowish white, the centers of the 

 whorls being fuscous; the shaft of the antennae has a decidedly 

 annulated appearance; eyes black; thorax with three pale yel- 

 lowish brown abbreviated, broad lines, the middle one originat- 

 ing before and terminating at the center of the disk, the lateral 

 ones originating rather before the middle; feet with numerous 

 small brown punctures; wings with many very obvious brown 

 spots. 



Size of C. c u 1 i c i f o r m i s Degeer (i. c. 6mm ) 



