HAGENIUS. 



11. Gomphoides species. 



There are three female nymplnv, not quite full grown, belonging to 

 a different species, similar to the foregoing and somewhat smaller, dif- 

 fering in having dorsal spines on segments 4 to 9. Locality : Rio dos 

 Macacos. Brazil. Thayer Ex. Mus. Comp. Zobl. 



HAGENIUS. 



Selys, Monogr. des Gompli., p. 238. 



Body exceedingly flat, nearly circular. Head cordate. Eyes set at 

 back of head. Antennae very peculiar ; two basal joints short, cylindri- 

 cal ; 3d flat, dilated, plate-shaped ; 4th very rudimentary, not to be 

 seen unless much magnified. Mask extending to fore legs, square, flat, 

 bent up at sides, front border produced at middle. Palpi small, inner 

 border not denticulated, tip rounded, blunt ; movable hook sharp, 

 somewhat longer than palpus. Middle legs more separated at base 

 than fore legs ; formed for running. Abdomen very flat, enlarged, 

 nearly circular. The outer edges of segments forming a sharp-edged 

 border, separated from abdomen by marked ventral ridge. 9th seg- 

 ment longer than 8th. 10th small, cylindrical, and entirely inserted in 

 9th. Anal appendices a little longer than 10th segment, 



12. Hagenius brevistylus. 



Selys, Monogr. des Gomph., p. 241, Xo. 86. 



Plate IH., fig. 4, a, c, d. 



Locality : North America. I have seen 8 nymphae, very young and 

 full grown, length, 12 mm. 40 mm., from Massachusetts, New York, and 

 Osage, Kansas, all females. In the collection of the late Dr. T. W. 

 Harris, in the Boston S. N. H, is preserved the skin of a nympha with 

 the imago raised by him. Coll. Mus. Comp. Zobl. Coll. Harris. Coll. 

 Hagen. 



Body very flat, broad. Head cordate, flat, breadth and length equal ; 

 between the antennae a narrow projection, with rectangular notch at 

 front, inserted in which a cordate tubercle. Eyes situated at hind part 

 of head, moderately large. Antenna? short, broad ; the 2 basal joints 

 short, 3d much dilated, flat, circular, with inner edge cut straight ; 

 border somewhat elevated, covered with short scale-like hairs ; at the 



