JESCHNA CCERULEA, A BOREAL DRAGON-FLY 27 



lateral valleys went right to the watershed between Glen 

 Lochay and Glen Lyon. There is therefore little doubt that 

 it occurs in Glen Lyon, as I indicated (" E. M. M.," vol. xxxi. 

 p. 260) it probably would. It was also found quite near 

 the watershed between Glen Lochay and Glen Dochart, and 

 although it may not be quite safe to assume that it also 

 occurs in Dochart, there is no reason why it should not. 



The area of its known distribution may be defined thus : 



The north side of Loch Rannoch (including the lower 

 part of the Ericht valley) ; how far eastward it goes on this 

 line is uncertain, but westward it has been observed near 

 Dunan. On the south side of the Loch it has been found 

 chiefly about the Black Wood ; but there is good reason to 

 suppose that it is well distributed over the country due south 

 of Loch Rannoch, passing into Glen Lyon, and thence to the 

 south side of Glen Lochay. 



Beyond these limits, it is impossible to conjecture what 

 its range is. It was not met with at all during a month's 

 stay in the Rothiemurchus and Glenmore district of Speyside 

 in 1896, although I kept a special outlook for it; nor did 

 Mr. King, who was in the district at the same time, see it then 

 or on previous visits to this and to the Kingussie districts. 

 From the country to the west and south-west of Rannoch 

 and Glen Lochay it has so far never been obtained, King 

 having failed to find it during sojourns at Glen Orchy and 

 Dalmally in different summers. 



Not only ^\ coerulea, but SE. juncea and Cordulegaster 

 annulatus range high up the hillsides, following the course 

 of the burns to their sources. There is no physical barrier 

 to a much wider distribution of cccrulea ; climate does not 

 stand in the way, and its powers of flight are more than 

 sufficient to carry it over any pass and to make it as wide- 

 spread as the other two. But dragon-flies are very local. 



The normal time of appearance of cccrulea seems to be 

 about the middle of June, although in some seasons it may 

 be out rather earlier. In Glen Lochay, during the past 

 summer, it was flying freely over the lower grounds up till 

 about the 8th of July, when it practically vanished there- 

 from, although it continued to be seen over 1000 feet, both 

 along the burns and on peat-bogs, until at least 25th July. 



