EXPLANATION OF FIGUEES. 



The following- figures illustratiug- some of tlie new experiments 

 on tlie rate of growth are reproductions of life-size photographs 

 of species which have been preserved in the same order as they 

 are arranged in the figures, and can thus l)e referred to any time. 



Plate I. 



Fig. 1. Clams of " Artificial Set " caught from swimming larvae 

 (page 2G). Dug and preserved, August 14, 1900. 



Fig. 2. Clams of " Artificial Set " reared in sand-box August 

 14 to September 8, at house-boat (page 43). 



