ODONATA OF THE VICINITY OF GO HOME BAY 55 



SESSIONAL PAPER No. 39b 



the rocky shores or fly about over the islands and the open channels. These are 

 all found also in the Go Home River, but characteristic river species are conspic- 

 uously lacking. 



Another noticeable feature of the fauna is the great abundance in the sphag- 

 num bogs at the edge of small lakes and ponds, of certain species that we have 

 met with rarely or not at all elsewhere in Ontario. The most characteristic species 

 of this group are Nehalennia gracilis, Nannothemis bella and Leucorrhinia frigida. 



Ecological Distribution of Species. 



The Odonata of the vicinity of Go Home Bay may be roughly divided into 

 three principal ecological groups, according to the nature of their breeding-places, 

 viz., 



Group 1 : — Species inhabiting the well-aerated waters of the open bay and 

 broader parts of the river. 



Group 2: — Species inhabiting still waters, e.g., shallow bays, sluggish creeka 

 in open marshes, small enclosed lakes and ponds. 



Group 3 : — Species inhabiting woodland creeks. 



Two other groups might be added, namely, those species inhabiting the rapids 

 and those breeding in the shallow sand-bottomed lagoons on the Giant's Tomb 

 Island (Fig. 36), but no characteristic species have been found in the former, 

 while the latter are for the most part identical with Group 2, there being but one 

 or possibly two peculiar species. 



These groups are not sharply distinguishable from one another, many species 

 fall into more than one of them. 



Group I. 



These species may be further subdivided into two groups, (a) those which 

 breed on exposed rocky shores, occurring also about the edges of currents (Figs. 

 26, 27, 28) and, (b) those which are inclined to occupy the lower, shallower and 

 more sheltered parts of otherwise exposed shores (Fig. 29, 30). These sub-groups 

 are not sharply separable, some species being equally well-placed in either. 



(a) 



1. Argia moesta putrida. 



2. Gomphus brevis. 



3. " lividus. 



4. Dromogomphus spinosus. 



5. Boyeria grafiana. 



6. Basiseschna Janata. 



7. Macromia illinoiensis. 



8. Didymops transversa. 



9. Neurocordulia yamaskanensis. 



