PROGOMPHUS. 7 



sions on occiput. Mask extending to fore legs, narrow ; length twice 

 the breadth ; somewhat enlarged forward, with middle channel widen- 

 ing forward ; front border produced in semicircular lobe, edged with 

 hairy comb ; the hairs forming this are enlarged at tip and flattened, 

 inserted in small basal cylinder. Palpi short, bent, ending in blunt 

 hooks, smooth inside ; movable hooks long, shar^i. Prothorax nearly 

 circular, rounded at fore-border, with two oblique impressions ; side- 

 border very slightly raised ; prothorax polished, shining, near borders 

 and middle line slightly granulated. Wing-cases extending beyond 

 4th segment. Legs stout, short, hairy, typical burrowing legs. 

 Hind legs much more widely separated at base than fore and middle 

 legs ; middle legs nearer at bage than fore legs. Fore legs somewhat 

 stronger than middle legs, the cox£e being highly developed, and the 

 femora triangular, arcuated and dilated at base. Tibife thickened at 

 middle, near the end bent and narrowed ; tarsi somewhat shorter and 

 bent up ; 1st joint ver}^ short, 2d long, knife-shaped ; hooks stout, 

 rather blunt, outer hook rather shortest. Middle legs similar in shape, 

 cox£e smaller, femora narrowed at base. Hind legs reaching 8th seg- 

 ment, similar in shape to the other legs, flatter. Tarsi 3-jointed, longer 

 than tibire ; claws sharp. 



Abdomen as in ^schna, venter flattened, dorsum rounded, largest at 

 5th segment, tapering toward end. Segments 1 to 9 with strong dor- 

 sal hooks. Side-border sharp. Segments 5 to 9 have lateral spines. 

 9th and 10th ventral segments not hollowed beneath, polished. The 

 three anal appendices rather longer than 10 segment, pyramidal, sharp, 

 of equal length ; two lateral ones half as long, blunt, pyramidal. 



This nympha is distinguished by highly develoj^ed burrowing legs, 

 fore legs strongest ; coxae, femora, and tarsi much developed. Middle 

 legs are nearest together at base, a peculiarity also distinguishable in 

 Gomphoides. Hind legs highly developed. Abdomen exactly like 

 ^schna. Segments of equal length, 10th perhaps a little shorter. 

 Ventral 9th not making part of the hollow of rest of abdomen ; stig- 

 mata placed outside of hind angles of prothorax. Shape of antennae 

 and mask refer this nympha to Legion Gomphoides. It might be sup- 

 posed to belong to genus Progomphus, if that genus were found in New 

 England. 



A female nympha not fully grown, 25 mm. length, precisely like fore- 

 going, but darker in color, from Carundahy, Brazil, Thayer Exp., is in 

 the coll., unless some mistake in locality has been made in the label. 



