164 REPORT OF COMMISSIONERS OF INLAND FISHERIES. 



rapid than that of Homarus americanus. This hypothesis will per- 

 mit of demonstration in the course of the succeeding pages. 



IV. Observations at Wickford on the First Ten Stages of 

 THE Lobster. 



The observations made at the Wickford Station of the Rhode Island 

 Fish Commission by the writer and others, though differing to some 

 extent from the results obtained by Herrick at Woods Hole, and 

 from those of other investigators working with Homarus vulgaris, 

 may serve to throw further light upon the rate of growth of lobsters 

 under natural conditions of environtnent, and perhaps give some hint 

 as to the value of a few of the conditions which appear to modify it. 

 Attention may be first directed to Tables Nos. 25 and 26. The ob- 

 servations here recorded were made upon young lobsters in stages 1 

 to 12, whose approximate age and definite stage were known. In- 

 dividual records were started immediately after the molt from the 

 third to the fourth stage and carried through the following stages 

 until the last of November. The records include observations upon 

 individuals many of which did not live through the later stages be- 

 cause of inadecjuate methods of preservation during the winter 

 months. A sufficient number, how^ever, were brought to the twelfth 

 stage to give some value to the data on the average size and usual 

 duration of the stage periods at this time of life. 



To determine precisely the rate of growth of lobsters in the first 

 three stages, few special observations have been made. This is 

 because of the fact that when these young lobsters are isolated in 

 glass dishes or other receptacles, for particular observation, the rate 

 of growth does not appear to be the same as under natural con- 

 ditions, but somewhat decreased. For this reason the most valuable 

 data on the rate of growth of lobsters in the first three stages are 

 gained from observations upon large numbers of lobsters in these 

 stages, which have been hatched at approximately the same time 

 and develop under more natural conditions in the large hatching 

 bags. In order, then, to represent the average rate of development 



