THE CANADIAN ENTOMOLOGIST 235 



Text fig. 10, 1-8 show the variation in the appendages of 

 the four known males of this rare species. 



This is evidently a very northern species as the known speci- 

 mens are from Newfoundland, Labrador and Hudson's Bay. 

 The vulvar lamina of the type female in the M. C. Z. is similar 

 to that of the albicincta female but not as deeply notched, being 

 less than a third the length of the lamina. The female, can be dis- 

 tinguished by her very small size, for the abdomen of this type 

 is but 30 mm. in length. 



The following specimens are in American collections, cf, 

 Grand Lake, Newfoundland; 9 , Bay of Islands, Newfoundland, in 

 collection of Williamson; cf , Stag Island, Rupert Bay, Hudson's 

 Bay, in Carnegie Museum; cf, type, Labrador; cf, Labrador; 

 9 , type, Labrador, in the Museum of Comparative Zoology. 

 See also figs. 17-20. 



Somatochlora cingulata (Selys). 



This is the. largest and finest of all the American Somato- 

 chloras. It is interesting in that in her great robustness the 

 female develops tubercles at the base of her appendages similar 

 in position to those on the male. What is probably a similar 

 assumption of male characters by robust females occurs in another 

 species of Somatochlora not in this cingulata group. In a letter 

 to Dr. Walker I suggested it might be due to a great abundance 

 of food, while Dr. Walker had data that would indicate it to be 

 due to climatic differences. 



Besides a male, and I think a female, in the M. C. Z. collec- 

 tion, whose labels I neglected to copy, the following specimens 

 occur in the collections I have had the privilege of studying, cf , 

 Bay of Islands, Newfoundland, and 9 , Grand Lake, Newfound- 

 land, in Mr. Williamson's collection, cf and 9 , St. Ignace Isl., 

 Lake Superior, and a 9 , from Orient Bay, Lake Nipigon, Ontario, 

 in the Carnegie Museum. See figs. 21-24. 



Explanation of Plate XIII. 



Figs. 5-8. Somatochlora hudsonica, male and female types^ 

 M. C. Z. Ft. Resolution, Mackenzie, Kennicott, 1861. 



