ORTHOPIEKA OF NOVA SCOTIA. PIERS. 



311 



Field Key to Nova Scotian Species of Scudderia. 

 Males. 



The following condensed key may be used as a more ready but cruder 

 means of separating our male Scudderia: — 



a. Notch in end of spine on upper side of extremity of body (supra-anal 

 spine) rather shallow and acute or V-shaped, the two branches of the 

 fork not swollen. 



b. Greatest width of wing-cover over 8 mm. (ends of branches of fork 

 gently tapering) -. 20. pintillata, p. 312. 



bb. Greatest width of wing-cover under 8 mm. (ends of branches of fork 

 of about equal width) 21. curvicauda borealis, p. 317. 



aa. Notch in end of spine on upper side of extremity of body very deep and 

 well rounded or U-shaped, each branch of the fork very much swollen. 



22. furcata furcata, p. 320. 



Females. 



The following key may serve to distinguish our female Scudderia: — 



a. Disk of pronotum with sides distinctly widening posteriorly. 



b. Wing-covers relatively broader, over 8 mm. in greatest width, their 

 proportions being about 1 to 3; eyes smaller. .20. pislillata, p. 312. 



b. Wing-covers relatively narrower, under 8 mm. in greatest width, 



their proportions being about 1 to 43^; eyes larger 



21. curvicauda borealis, p. 317. 



aa. Disk of pronotuin with sides nearly parallel; wing-covers narrow, their 

 proportions being about 1 to 45^ .... 22. furcata furcata, p. 320. 



The ovipositors of the three forms closely resemble each other, although 

 that oi furcata is relatively narrower than that of the other two. Identification 

 by ovipositor is very difficult with these insects and must be done with the 

 greatest caution by a beginner. 



S.pistillata 



3. curvicauda borealis 



tS. furcata furoaba. 



Distinguishing Forms of Supra-.inal Spine? of Males of Species of Scudderia. 

 (Enlarged about 5 times.) 



The first three figures show the spine aa viewed from above, the fourth in a lateral 

 view. The figure of S. p stillata i.s from a .=pecimen collected at Halifax, that of S- curvicauda 

 borealis is from one collected at Wilmot, N. S., on (i Sept. 191.5, and that of S. furcata furcata 

 I rem one taken at Chocolate Lake, Halifax, on 30 Sept. 1917. 



