FISHES 



and no pairing was observed in the evening, at night, or early 

 in the morning. 



Mr. Holt obtained additional specimens of the fish, and these 

 were placed in the same tank, from which all other kinds of 

 fish were removed to facilitate observation. The new females 

 obtained, however, seemed all to die. On March 8, sexual 

 activity again commenced. Only one female was engaged at 

 this period also, and if not the same individual which was 

 watched on the previous occasions, was of about the same size. 

 Besides the two males which paired in the previous month, 

 there were now three others with fully developed sexual 

 characters. None of the five were in very brilliant colour, 

 and one in particular, believed to belong to the original stock, 

 had lost nearly all the bright yellow of the bands on the body. 



Mr. Holt watched the behaviour of these five males and 

 one female, to ascertain what evidence of selection on the 

 part of the female could be observed. Of the five males, 

 1 and 2 were large, 3 and 4 rather smaller, but as well 

 developed in colour and characters of the fins, 5 was large 

 but dull in colour. The last of these made no demonstrations, 

 he swam away from the others which approached him, and at 

 last buried himself in the gravel. The fourth was not seen 

 near the female. There were thus three males left which 

 showed sexual excitement. 1 was seen to ascend with the 

 female, they then descended to the ground near 2. The latter 

 displayed several times before the female, while 1 lay still, 

 breathing rapidly and taking no notice ; he was evidently 

 fatigued. The second male and the female took hold of each 

 other and began to ascend, when the first set up his fins and 

 darted under them, brushing their ventral surfaces with his 

 long first dorsal. But this had no effect on them, and they 

 made the ascent in the usual manner. 



After this the first male was about to ascend with the 

 female again, when the third approached and displayed. The 



