148 
The Ohio Naturalist. 
[Vol. VII, No. 7 , 
females were taken of this very abundant species. There is a 
disposition to regard rubieundulum 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 rubieundulum. 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 30th. 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 savi, 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 constrieta, 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 that it is possible many of the 
eastern species of Somatochlora may eventually be found on the western 
coast also. 
