METHOD OF STUDYING THE LIFE HISTORY OF FISHES. II4I 



clung tenaciously to every branch it touched. Along the cord were large numbers of 

 small eggs. When 4 or 5 inches of the cord had been attached, the fish would rest, 

 the male taking her place and hovering over the eggs, which he guarded with a vicious- 

 ness altogether unexpected in so small a fish. He withdrew when his mate resumed 

 egg laying. She frequently pushed her way through the clump of weed, but more often 

 passed around it, the silken tenacious cord binding it together in a globular or oval 

 mass about the size of a hen's egg. The entire nest * * * was formed in about 

 two hours, the fish dropping to the bottom of the tank after each effort and lying there 

 for ten or twenty minutes. 



I had taken a series of photographs of the nest, and by removing the eggs to a 

 glass globe, in turn placing them in the interior of the large tank so that they 

 VFOuld not be disturbed, I soon had the young for examination. 



This seems to me the simplest method of observation, namely, open, free, 

 well-lighted tanks, with large skylight, so that the natural conditions of the 

 ocean are more or less obtained; aeration from above, so arranged that it can 

 be increased in the case of surf fishes, or decreased for deep-water forms; special 

 tank for photographing fish at various stages of development, etc., at once 

 simple and productive of results of value to students or laymen. 



