sen 



MIGRATION AND FOOD. 



in their turn becoming a prey to tlie larger species. As the eggs of 

 marine invertebrates are deposited at the same' time as those of many fishes, 

 the fry of the latter find minute food (the young of the former) ready for- 

 their wants, so fine, indeed, that they are only obtained by straining the water 

 through gill-rakers. 



