Vol. Xxii] ENTOMOLOGICAL NEWS. 345 



and squarely notched behind between wide hind angles that are 

 obtusely rounded externally and beset with minute prickles or tuber- 

 culations. Antennae seven-jointed, the relative length of the segments 

 being as i : 1.6 : 2 : 1.9 : 1.6 : 1.2 : .6. 



The legs are short and rather stout with spinulous longitudinal 

 carinae. The femora show indistinct subapical rings of paler colora- 

 tion. The wing-cases reach the middle of the fourth abdominal seg- 

 ment. Abdomen rather short, cylindric, slightly tapering posteriorly, 

 with a row of pale dots across the apical border of each segment. 

 Gills oval, widest just beyond the middle, tapering to both ends, but 

 more abruptly to the submucronate apex. They are without the 

 middle transverse suture of the preceding species, but they retain 

 the chitinized margins bearing minute serratures and spinules in 

 something less than the basal half of the dorsal margin of the 

 superior gill and of the ventral margin of the paired gills. The 

 tracheal branches are all long. They issue separately near the base 

 and gradually diverge as they pass outward along the axial thicken- 

 ing of the gill. 



The genitalia are well marked in both sexes. The ovipositor of 

 the female is large, its supporting valves bear on the ventral margin 

 several spinules and have a thorn-like decurved apex. The ninth 

 segment in the male is armed ventrally with two sharp pyramidal 

 triangular spines. 



I have ventured to publish these brief descriptions for the 

 purpose of calling attention to the cleft condition of the 

 labium in two true Agrioninae. Also, for the purpose of calling 

 attention to the almost untouched problem of the segmenta- 

 tion of the caudal gills which the three forms herewith describ- 

 ed present. The first of these has gills with a short basal 

 segment, something as in Lestes. The second has a distinct 

 joint in the middle of the gill. The third has lost the middle 

 suture, but has retained a slight differentiation of the margin 

 of the basal portion, as have some other well known agrionine 

 nymphs. 



Explanation of Plate XL — Figures i to 4, unknown nymph of iho 

 legion Podagrion. i — The head from above. 2 — The lal)iu-.i.i from 

 within. 3 — The lateral lobe of the same. 4 — A single caudal gill. 



Figures 5 to S~Psettdagrion (supposition). 5 — The head from 

 above. 6 — The labium from within. 7 — The lateral lobe of the 

 same. 8 — The end of the abdomen of the male nymph, showing 

 gills. 



Figures 9 and 10 — Aciagrion (supposition). 9 — The labium from 

 within. 10 — The lateral lobe of the labium of the same. 



