NATURAI^ HISTORY OF AMERICAN LOBSTER. 

 Table io. — Production of Eggs. 



299 



In table 10 (reproduced from 149) we have given the smallest, largest, and aver- 

 age number of eggs removed from the bodies of 4,645 individuals. These animals were 

 "old" egg lobsters and were caught in Vineyard Sound and vicinity from April to 

 June. The numbers were determined as a basis of 6,440 eggs to the fluid ounce. These 

 tabulated results show great variability in the number of eggs borne by individuals 

 of the same length, which may be attributed in part to loss of ova, but more to varia- 

 tion in the period of sexual maturity. Thus in 514 lobsters of the lo-inch length the 

 number of external eggs varied from 3,045 to 24,360, with an average of 10,555. ^or 

 the 12-inch size the corresponding numbers were 3,045, 54,810, and 21,351. We have 

 seen that the period of sexual maturity is exceedingly variable in different individuals 

 and that one animal may lay its first batch of eggs when 7 inches long, while another 

 may not rear a brood until its body is 5 inches longer and has increased greatly in vol- 

 ume. The phenomenon is not remarkable in view of the slow growth of the ova, but 

 it is important to recognize the fact. 



Consideration of the average number of eggs produced suggested a general tend- 

 ency which was expressed as follows : The number of eggs produced at each reproductive 

 period tends to vary in a geometrical ratio, while the lengths of the animals producing 

 these eggs vary in an arithmetical ratio. The average production in lobsters 8 inches 

 long being 5,000 eggs, the average product for lobsters 10 inches long would be 10,000; 

 for the 1 2 -inch length, 20,000. This high rate of production is not maintained beyond 

 the length of 14-16 inches. The lobsters with the largest number of eggs measured 

 from 15 to 16 inches in length and carried upward of 97,000 eggs, which measured 

 16 fluid ounces and weighed nearly a pound. 



I^ataste ( J77) in a c ritical paper on that section of my earlier work dealing with 



^the fecundity of this animal observes that the number of eggs carried by the lobste r 



at anv given time should be proportional to the volume of the body or to the cube 



of its length. If N represents the number of pp-ys carried. / the length of the animal. 



