194 CONNECTICUT GEOL. AND NAT. HIST. SURVEY [Bull. 



wing much like other Aeschnidae, particularly Aeshna species. 

 The only specimen in the collection of the Experiment Station was 

 taken at Litchfield along the slow-flowing outlet of Bantam Lake. 

 The species was found flying back and forth over a given "beat," 

 keeping well to the middle of the stream. In contrast to most 

 other Aeshnids, the species is apparently most common in June or 

 the early part of the summer. 



Nasiaeschna pentacantha Rambur 



Histoire naturelle des insectes. Neuropteres, 208: 1842. 



Nymph (PI. iii, Fig. 2). — Color very dark brown, tarsal seg- 

 ments yellowish. 



Head : labium with mentum extending between the mesocoxae, 

 the median lobe with a closed median cleft, and setose distal 

 margin ; proximal segments of palpi with blunt projections pro- 

 vided with an inturned hook at apex and with small rounded 

 teeth on the mesal margins ; antennae with the 6th segment long- 

 est, segments 3-6 being pale with apices of 5 and 6 dark ; two 

 tubercles on the head about i mm. above the bases of the antennae, 

 and separated from one another by less than i mm. ; the lateral 

 margins of the head each with a similar tubercle; dorso-lateral 

 angles of the eyes separated by about 1.5 mm. 



Thorax: pronotum with four distinct elevations on the dorsal 

 surface, the lateral margins flaring; propleura with two blunt 

 projections above each procoxa. Meso- and metapleura also with 

 several slight elevations resembling tubercles and projections 

 (smaller than those over procoxae) above meso- and metacoxae; 

 legs distinctly carinate, especially the femora, which are sometimes 

 also provided with furrows. 



Abdomen: lateral keels with spinous projections on segments 

 5-9 inclusive, and mid-dorsal projections on segment 5 or 6-9; 

 anal appendages consisting of very short laterals (less than i mm.) 

 and much longer dorsal and ventral appendages, approximately 

 3 mm. in the specimen studied. 



Cuticle decidedly granular in appearance under the microscope, 

 due to minute setae. 



Measurements ; immature nymph : total length, yj mm. ; abdo- 

 men, 25 mm. ; greatest width, 7 mm. ; hind femur, 4.5 mm. ; 

 width of head across the eyes, 7 mm. ; mentum, 6 mm. long by 

 2.5-4.5 mm. wide; length of metathoracic wing-cases, 4.5 mm. 



Described from a specimen obtained from Dr. P. P. Calvert, 

 taken at Go Home Bay, Ontario, Canada, 1909. 



Adult, male (PI. xviii, a). — Color dark brown marked with 

 green. 



Head : clypeus, labrum and labium light green ; cephalic surface 

 of front green, dorsal surface bluish, vertex and occiput dark 

 brown, postgenae lighter on sides; antennae black; compound 



