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BULLETIN OF THE BUREAU OF FISHERIES. 



Table 9. — Record of the Total, Catch op Lobsters in the Harbor op Woods Hole, Mass., 

 FROM December i, 1893, to June 30, 1894, Showing the Number and Size op Egg-bearing 

 Females. 



The reproductive curve, based upon body length, is seen to begin with the 7-inch 

 lobster and to rise very slowly between this and the 9-inch size. 



We do not assume that lobsters are always uniformly distributed, or that had the 

 experiment been conducted elsewhere the results would not have been somewhat dif- 

 ferent. Where thousands of lobsters are captured at any point a considerable number 

 measuring 8 inches or less may be found to have eggs outside of the body, but the 

 proportion of this number to the total number of animals of the same length captured 

 in the same place for the entire period will undoubtedly be very small. 



LIMITS OF THE BREEDING SEASON. 



Much confusion formerly existed concerning the time when the lobsters laid their 

 eggs. This arose mainly from the fact that the eggs are carried by the females for a 

 period of 10 months before they are hatched, and because of occasional departures 

 from the common rule to which the majority conform. The following conclusion was 

 reached in 1895: "About 80 per cent of spawning females lay their eggs at a definite 

 season in the summer months, chiefly in July and August. The remainder, about 20 

 per cent of the whole number, extrude eggs at other seasons, in the fall and winter 

 certainly, and possibly also in the spring." While this statement seems to me now to 

 be in the main correct, I consider it very probable that considerably less than 20 per 

 cent of the whole number of spawners lay eggs out of season, as was then suggested. 

 It is not necessary to review the data by which it was definitely proved that eggs are 

 at least occasionally deposited in winter and fall. The only way to check these results 

 is to determine the retarding influence of a temperature varying from 67.1° to 32.1° F. 

 (September to February, Woods Hole, Mass.) upon different batches of eggs laid out 

 of the usual season. When normal eggs in the egg-nauplius stage, which in summer 



