THE 1MMATI 111. si A IF. OF THE I NAI'A. 33 



tubercles, bul on each side four ovoid flal spaces, with a rough stripe in 

 these spaces ; vertex more inflated, <>n each side with a blackish impression ; 

 antennas with 2d joinl longer, 3d a little longer than 2d : 5th in 7th equal, 

 as long as 3d; side lobe of prothorax sharp, benf upwards; v.in. 

 reaching half of 7th segment; abdomen smooth, lateral spines on segment 

 s \<t\ short, "ii Jili long, sharp, flat, longer than segmenl 10; dorsal hooks 

 on segments 6 to 'J, sharp backward-bent Bpines, successively longer, the 

 last longer than segment 10; anal appendages a- long a- segments '.' ami L0, 

 trigonal, sharp; dorsal median a little shorten- than inferiors; laterals as 

 long as the dorsal median, thick, tip suddenly sharpened ; legs longer, 

 thinner, femur of hind legs reaching segment 8. tibia of same legs black, 

 pale at base and four pale wings near tip; first joint of hind tarsus one third 

 shorter than second. 



21. CORDULIA ALBICINCTA tin. (Supposition.) 

 Plate V. Fig. 1. 



A large number of young and nearly full-grown nymphae from Her- 

 mit Lake. White Mountains, collected, July, 1875. by II. Morrison, and 

 June, by Fr. Sanborn. Length, 11 to 22 mm.; breadth. 8} mm. 



Body oblong, enlarged and truncate behind ; dark brown, very hairj ; 

 head short, visibly narrower than the abdomen, diamond-shaped ; about 

 half as long as broad; eyes not much pointed; waved transverse line 

 very little marked ; head before the antennas yellowish ; antennas long, 

 yellowish, the two basal joints a little thicker, length of joints as in 

 C. metallica ; mask spoon-shaped, yellow, seven close interlocking teeth on 

 the palpus; nine long, yellow movable spines each side internally along 

 the mask, and similar ones along the inner border of palpus; movable 

 hook short, very slnrp ; head behind the eyes dull, rough in some places; 

 at each side and in the hind corner a bunch of irregular stiff bristles. 



Prothorax narrower than the head ; hind border triangular, with an 

 inflated rim ; sides with a small elliptical lobe bent upwards ; stigmata long, 

 free ; wing cases reaching the 7th segment ; abdomen once longer than 

 broad, roof-shaped, a little sloping before the tip, which is truncate ; lat- 

 eral spines on 8th and 9th segments flat, very short, sharp, a little incurved ; 

 no dorsal hooks, even no indications of them, but a bunch of longer hairs ; 

 last segment anuliform ; the other segments of equal length ; anal ap- 



