416 NEW YORK STATE JIUSEUII 



Air tube 4 or 5 times as long as broad (6> 



5 Tube concave, the tip wider tban tlie terminal portion. 



Spines of tube mostly with a single basal branch territans 



Tube regularly tapered, smallest at the tip. Spines of tlie 

 tube 3 to 4 branched n i g r i t u 1 u s 



6 Anal segment without hair tufts anteriorly of the trans- 



versely barred area (7) 



Anal segment with hair tufts on the ventral line up to the 

 base d y a r 1 



7 Lateral comb of the eighth segment a patch of spines; tube 



brown p i p i e n s 



Lateral comb a row of bars; air tube black. .; melanurus 



8 Apex of the labium rounded [pl.44, fig.l]. Antennae whit- 



ish on basal half : restuans 



Apex of labium pointed [pl.45] cantans 



9 Lateral comb of the eighth segment a patch of small spinesi 



three or more rows deep (10> 



Lateral comb a few spines on a single or partly double row (13) 



10 Anal segment with hair tufts before the barred area (11) 



Anal segment without tufts before the barred area (12) 



11 The spines of the air tube prolonged into setae; tube about 



three times as long as wide; the antennal tuft is at the mid- 

 dle of the joint consobrinus 



The air tube with spines, anal segment broadly plated, .canadensis 



12 Antenna with a small tuft a little before middle of the joint. 



Air tube about two and a half times as long as wide; 



lateral comb about three rows deep bimaculatus 



Antenna with a single inconspicuous hair instead of a tuft. 

 Air tube not over twice as long as wide; lateral comb 

 about five rows deep .atropalpus 



13 Anal segment with hair tufts before barred area (14) 



Anal segment without tufts before barred area (16> 



14 Comb of eighth segment of separate nearly, simple spines, 



the spines of the air tube each with three teeth s y 1 v e s t r i s 



Comb of eighth segment either toothed or digitate (15) 



15 Comb of eight segment composed of spines with finely digi- 



tately divided tips; antenna with a single long seta instead 



of a tuft , triseriatua 



Comb of conspicuously toothed spines, joined on a weak 

 basal plate. Antenna with a small hair tuft j a m a i c e n s i s 



16 Comb of eighth segment of nearly simple, thorn-shaped 



teeth sollicitans 



Comb of eighth segment of pectinated spines in aa incom- 

 plete double row taeniorhynchus 



The pupae resemble each other so closely that I have been 

 unable as yet to find satisfactory characters to distinguish them. 



