DO NAT A OF THE VICINITY OF GO HOME BAY 73 



SESSIONAL PAPER No. 39b 



,28, Dromogomphus spinosus Selys. 



On July 5, 1907, a newly-emerged male of this species with its exuvia was 

 found on the Station Island. A few other exuviae were also found here subsequently 

 and adults were occasionally observed though not frequently. They were appar- 

 ently much more numerous on the river above the Chute, judging from the large 

 number of exuvisB found there. 



In 1912 we did not come across this species at all, but Mr. Wodehouse dredged 

 up a number of nymphs of various stages from Shawanaga Bay and the Shawan- 

 aga River on June 9 and 13, including several full-grown ones. Those from Shawan- 

 aga Bay were taken from weedy shallow water with a sandy bottom. Usually the 

 nymph occurs where there is little aquatic vegetation. This is the case at De 

 Grassi Point, Lake Simcoe, where this species is the only common Gomphine. 

 Here it lives in a bottom of very fine sand and transforms on the boulders along 

 the shore. The imagoes fly freely over the water and often settle on passing boats 

 and on the boulders of the shore. They may also be taken quite fiequently on 

 roads through the woods within a few hundred yards of the lake. 



29. Boyeria grafiana Williamson. 



This is one of the late-appearing dragonflies, August being the month in which 

 it is most abundant. Full-grown nymphs were collected on and after June 4, and 

 the first adult emerged in the laboratory on July 14, followed by several others 

 during the succeeding fortnight. 



Teneral adults are often found clinging to the trunks of trees or the sides of 

 houses in the shelter of the verandah. When mature they may be seen flying up 

 and down the lake shore, close to the water, and following a more or less regular 

 beat. Sometimes this is limited to a little cove two or three yards across, but 

 generally they cover a much greater distance at a time. 



They are most active in the evening, but fly also during the day. In their 

 crepuscular habits they recall Neurocordulia yamaskanensis which they also re- 

 semble a good deal in general appearance, especially in the dull brownish coloration. 

 They are less swift than the latter, however, and their flight is practically re- 

 stricted to a narrow littoral zone. The season of adult life extends until about 

 the end of September. 



Williamson's description of the coloration of this species does not fit the ma- 

 jority of specimens that we have seen, in all respects. The light markings are bright 

 3^ellow at first, but become dull with age. I have never seen blue-spotted in- 

 dividuals such as those described by Williamson, but the colour is always distinct 

 from that of B. vinosa. The fulvous tone of the wings in the latter and the dark 

 markings at their bases are not seen in B. grafiana. 



The dark-coloured nymphs are found rather commonly under stones, along 

 more or less wave-beaten places or wherever there is a perceptible current. They 

 are generally distributed along the shores of Go Home Bay and River, except in 

 marshy places. They show a preference for the neighourhood of rapids or narrow 

 channels wherever there is a free circulation of water. They are perhaps most nu- 



