66 THE SMALL-MOUTHED BASS 



laying began. He occasionally bites the female. Since 

 egg laying began the female has become much darker, and 

 is now as dark as the male. Five successive intervals be- 

 tween the egg laying periods timed by the watch are found 

 to be 22 sees.; 28 sees.; 30 sees.; 32 sees.; 45 sees." 



"With the aid of a field glass the eggs, it is now thought, 

 may be seen issuing from the oviduct, but this is necessarily 

 uncertain. No milt can be seen, since the milt is colourless. 

 After a time the eggs are clearly seen adhering to the stones 

 of the nest bottom." 



"At 2.50 p.m., two hours and twenty minutes after the 

 fish entered the nest, the female leaves it, pursued by the 

 male. The male, no longer mottled, soon returns and takes 

 up his position over the nest. There he poises and fans the 

 eggs with his pectorals, but frequently goes outside the 

 nest and circles the immediate neighbourhood, as though 

 in search of possible enemies." 



I have described this case in detail because it is rare that 

 so good an opportunity offers for observing the spawning 

 behaviour of the bass. Mr. Lydell, who watched with me, 

 was of the opinion that the movements of the fish were less 

 vigorous than in other cases which he had observed, but 

 admitted that he had never had a better opportunity. The 

 eggs laid in this nest, after developing normally for about 

 two days, died, and this I can attribute to no other cause 

 than a lack of vigour on the part of one or both parents. 

 Yet the spawning behaviour of these fish was not seen to be 

 in any way different from that of the four other pairs that 

 were observed in a fragmentary way. 



In another case in which the spawning was watched the 

 female twice attempted to leave the nest, but was each 

 time pursued by the male, who took up a position outside 

 of her and bit her in such a way as to drive her into the 

 nest. At the third attempt she escaped and was not seen 

 to return. 



