ODONATA OF THE VICINITY OF GO HOME BAY 89 



SESSIONAL PAPER No. 39b 



Mr. Wodehouse) belong to this species.* They agree closely with Needham's 

 ('01) description which was based on a single collapsed exuvia, except in the fol- 

 lowing particulars: — The dorsal hooks are somewhat shorter than the segments 

 which bear them, the lateral spines of segs. 8 and 9 are also somewhat shorter than 

 is indicated in the description, those of seg. 8 being about one-third as long as the 

 segment, and those of 9 reaching only to the tips of the lateral appendages. 



Besides these specimens, I have a number of similar but smaller nymphs, 

 including two full-grown examples, from Fitzwilliam Island, Georgian Bay, col- 

 lected by Mr. Wodehouse. Besides the smaller size these differ in the slightly 

 shorter lateral spines of seg. 9. Specimens from Giant's Tomb Island are, however, 

 intermediate in this character which appears to be a rather variable one. The 

 number of mental and lateral setae is slightly smaller in the smaller nymphs, there 

 being 10-12 of the former and 9-10 of the latter, as compared with 13-15 mental 

 and 10-11 lateral setae in the larger specimens. The number of these setae, how- 

 ever, seems to depend a good deal on size, and we doubt if in this case any other 

 importance can be attached to the feature. It may be also noted in this connection 

 that adults of S. costiferum vary in size with locality, specimens from Northern 

 Ontario being distinctly smaller than those from farther south. 



Sympetnim vicinum (Hagen) Kirby. 



Full-grown nymphs of this species were collected towards the end of July 

 and in early August and were found to be generally distributed along the marshy 

 of boggy margins of still waters, their environment being similar to that of Leu- 

 corrhinia frigida. They were found, e.g., along the edges of sphagnum bogs as 

 well as in shallow reed-grown waters. 



The first imagos emerged on July 30 and by August 6 the pale yellow tenerals 

 were quite common in the marshes. In the latter half of August they had for the 

 most part acquired their bright red colour and were common everywhere. They 

 were still numerous when the Station was closed on Sept. 11th. Many pairs 

 were m copula at this time* 



A description of the nymph is given by Needham ('01). 



Sympetnim semicinctum (Say) Kirby. 



This pretty species is not rare, but never appears in large numbers, as do most 

 of the species of Sympetrum. Specimens were taken in open marshes adjoining 

 shallow bays and creeks, but nothing distinctive was learned of their habits or 

 haunts. 



The nymph, which has been described by Needham ('01) was not obtained 

 by us. 



The dates of our specimens range from July 24 (1912) to Aug. 24 (1907). 



^ *Since the above was written we have reared this species on Vancouver island and have 

 verified the above determination. 



