692 PROCEEDINGS OF THE XATIOXAL MUSEUM. vol. xxvii. 



GOMPHUS SOBRINUS Selys? 



Several exuvij^ were collected bv Prof. R. C. Osburn at Seattle, 

 Washington. Thi.s species occurs there, and is the only described 

 regional species to which nymphs of this type can be supposed to 

 belong. 



Length, 4(> mm.; abdomen. 27 mm.; hind femur. 5 mm.; width of 

 head, 6 mm.; of abdomen. S mm. 



Bod}^ elongate, depressed, smooth. Third segment of antenna hairy 

 along its edges, more than four times as long as the two ])asal. of 

 which the first is twice the second in size; fourth segment u minute 

 rudiment. Labium (Plate XLIII, tig. 4) rather broad, mentum slightl}' 

 widened anteriorly; median lobe slightly rounded on front margin 

 and densely fringed with hairlike scales; lateral lobe short, stout, 

 abruptly narrowed beyond the movable hook, where it is sharply 

 incurved to form the end hook, before which on the inner margin are 

 4-5 low. broad teeth, increasing in size proximally. Hind angles of 

 the head prominent, marked with narrow scars; hind margin with 

 three broader scars. 



Burrowing hooks small. Wing cases reaching the base of the 

 fourth abdominal segment. 



Dorsum of the abdomen with distinct impressed median line on 

 segments 3-6, a pair of transverse small brown spots on either side 

 the line on each of these segements; a tlat, triangular rudiment of a 

 dorsal hook on the apex of the ninth segment, perhaps also on the 

 eighth. Prominent lateral spines on segments 6-9, about equal in 

 size, those of segment !* one-third as long as the tenth segment. 

 Appendages longer than segment 10. and about equal in length each 

 to each. 



DROMOGOMPHUS SPOLIATUS Hagen. 



Exuvige, collected at Fort Wayne, Indiana, b}^ Mr. E. B. William- 

 son, July 16, 1901. Imagos were observed commonly, fl3'ing along 

 the canal at the same place and time. 



Length, 34 mm.; abdomen, 21 mm.; hind femur, 6.3 mm.; width of 

 head, 6 mm. ; of abdomen, 8 mm. 



Body little hairy, strongly depressed, widest across the middle of 

 the lanceolately pointed abdomen. Head depressed, wedge-shaped, 

 pointed anteriorly, the labrum nearl}^ covered by the appressed and 

 flattened antenna?. The two basal segments of the antenna are globu- 

 lar, the first a little larger, the third is more than twice as long as 

 both basal ones together, depressed and concave superiorly and 

 incurved at tip, and scurfy hair}^ on the thick margins, the fourth 

 segment a very minute ovoid rudiment. Labium (Plate XLIH, fig. 5) 

 moderate, hinge reaching posteriori}^ as far as the meso-thorax, the 

 mentum with parallel sides beyond the narrower basal third, the front 



