1908] The Dragoxfliks of the Ottawa District. 57 



or less spotted with yellow and with a large basal yellow spot 

 on the dorsum of seg. 7. 



This insect frequents woodland paths and glades in the 

 neighbourhood of large lakes and rapid streams, coursing swiftly 

 back and forth over, its chosen path with almost tireless energy. 

 It appears about the end of June or first week in July and remains 

 until the latter part of August. 



Genus Neurocordulia, Selys. Fig. 10. 



34. Neurocordulia yamaskanensis (Prov.), Selys. 



Ottawa, 1 male (Harrington). 



A dull bro\vn dragonfly about 53 mm. long, the hind wings 

 ha^•ing an amber-colored basal patch with dark-brown veins, 

 extending as far as the arculus. The short sector and upper 

 sector of the triangle in the fore wing are parallel, or slightly 

 divergent, a character wdiich distinguishes it from our other 

 Cordulinae in which they are m.ore or less convergent. 



This insect appears to be common in the region of lakes 

 between Georgian Bay and Ottaw^a. It frequents large lakes 

 or rivers and is unique among our dragonflies in its habit of 

 flying only after sunset, when the mayflies upon wdiich it feeds 

 are aV^road. 



Genus Epicordulia, Selys. 



35. Epicordulia prixceps (Hagen) Selys. 

 1 male, fragmentary (Maclaughlin). 



This large insect (hind wdng, male 41, female 44 mm.), is 

 marked like certain species of Libcllula, having a large dark- 

 brown triangular patch at the base of the hind wings, and some- 

 times a smaller basal spot on the fore wings, a nodal and an 

 apical spot. The nodal spot is often absent in the males in 

 northern latitudes, and the apical spot much reduced, and such 

 examples closely resemble an immense Tetragoneuna. 



It is a swift, restless species which is abroad during July 

 in the vicinity of lakes, often flying at a considerable height, 

 and frequently met w'ith over water some distance from the 

 shore. 



Genus Tetragoxeuria, Hagen. 



Dragonflies of moderate size with more or less black at the 

 base of the hind wings; only 4 anteculntals in the latter. Ab- 

 domen depressed with a row of dull yellow? dorsal spots along the 

 margins. The metalhc coloration of the thorax is largely 

 obscured by a dense growth of grayish hairs. 



36. Tetragoneuria CYNOSURA (Say), Selys. Figs. 11,12. 

 Ott£-wa, Mav ,SOr,h, l^v9, i female (^Gi't^sonj ; June 5th, iv03, 



1 male (Fletcher): Hull, June 29th, 1886. 1 male (Fletcher). 



