436 COLYMBID^E. 



perseveringly as the other species, and can remain long 

 submerged, making very great progress during its sub- 

 marine flight, as was experienced by Sir William Jardine 

 and myself, when in chase of this bird in a light and handy 

 boat upon Loch Awe. Our utmost exertion could never 

 bring us within range, and we were often foiled by its 

 returning on its former track, and re-appearing in a direc- 

 tion contrary to that in which it seemed to have dived. 

 During this pursuit it was frequently lost for several 

 minutes together, and came up nearly a quarter of a mile 

 ahead, and its progress could not, I should think, have 

 been much under the rate of eight miles in the hour. 

 It lives upon fish, aquatic insects, and such other food as it 

 procures under water. I have seen a pair upon Loch Awe 

 towards the end of June, but did not succeed in detecting 

 their place of nidification. When in Sutherlandshire we 

 found this species upon most of the lochs of the interior. 

 The first we noticed was at the foot of Loch Shin, where 

 we were so fortunate as to find the nest, or rather the 

 two eggs, upon the bare ground of a small islet, removed 

 about ten or twelve feet from the waters edge. The 

 female was seen in the act of incubation, sitting horizon- 

 tally, and not in an upright position, upon the eggs. In 

 plumage she precisely resembled the male, and when fired 

 at immediately swam, or rather dived off to him at a short 

 distance. Our pursuit after them was, however, inef- 

 fectual, though persevered in for a long time, as it was 

 impossible to calculate where they were likely to rise after 

 diving. Submersion frequently continued for nearly two 

 minutes at a time, and they generally re-appeared at 

 nearly a quarter of a mile's distance from the spot where 

 they had gone down. In no instance have I ever seen 

 them attempt to escape by taking wing. I may observe 

 that a visible track from the water to the eggs was made 



