148 The Ohio Naturalist. [Vol. VII, No. 7, 



females were taken of this very abundant species. There is a 

 disposition to regard rubicundulum and obtrusum as scarcely 

 _ distinct. I have examined a great amount of material, covering 

 practically the total range of the two and I have never seen a 

 specimen which could not be referred certainly to one or the 

 other on the basis of form of accessory genitalia of segment two. 

 Moreover, the ivory white face of mature obtrusum is in striking 

 contrast with the obscure face of rubicundulum. On the other 

 hand I do not regard assimilatum as worthy of a name. At 

 Stony Lake this species was very abundant, associated with the 

 three species of Leucorhinia. What is the significance of the 

 ivory face of the four? 



31. Sympetrum scoticum Donovan. Sault Ste. Marie, Onta- 

 rio, July 3Uth. A single female ; others were seen but I had but a 

 moment during a stop of the train. 



32. Libellula quadrimaculata Linne. Stony Lake, August 

 3d, three males. This species was common at Stony Lake, resting 

 on dead twigs over the water. It was seen at a number of places 

 along the railroad track in the Upper Peninsula of Michigan. 



LIST OF DRAGONFLIES OF CANADA. 



E. B. Williamson. 



The following papers published within the past few years 

 repeat most of the records of earlier authors and throw new light 

 on the distribution of northern North American dragonflies. In 

 addition to the species discussed in these recent papers and listed 

 below the following have been recorded from Canada: 



Cordulegaster sayi, Samatochlora franklini, Somatochlora 

 septentrionalis, Dorocordulia lintneri, Celithemis fasciata, and 

 Leucorhinia borealis. 



The portion of this vast land area west of the continental 

 divide is characterized among other features by the development 

 of the genus Sympetrum. The eastern portion, of much greater 

 extent, is characterized by a richer fauna and the great number 

 of Gomphines and of species of the genus Somatochlora.* Yet 

 the homogeneity of the fauna of the entire region, east and west, 

 is strikingly indicated by a comparison of the lists of species 

 known from Alaska and Newfoundland. The ten certainly 

 determined species known from Alaska are widely distributed 

 and, with the exception of one, Aeshna constricta, itself a very 

 common, widely distributed species, all are known to occur in 

 Newfoundland. Where homogeneity in the east and west regions 



* So few specimens have been taken tliat il is jiossible many of the 

 eastern species of Somatoc^ilora may eventually be found on the western 

 coast also. 



