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producing these eggs vary in an arithmetical series. According to this 

 law we have the following ; 

 Series of lengths : (in inches) 8 10 12 14 16 



Series of eggs : 5,000 10,000 20,000 40,000 80,000 



An examination of nearly a thousand cases shows that this law 

 usually holds good. 



The question of fertilization of the egg is a very difficult one, and 

 nothing is yet known of how the spermatozoon is conveyed to the egg, 

 and penetrates its membranes. We know, however that copulation 

 takes place in the spring and summer months , and probably at other 

 times of the year , that fertilization is effected outside of the body, 

 that the semen is stored in a peculiar pouch or receptacle , where it 

 may retain its vitality for months, at least. 



The eggs are carried, attached to the body of the female for a 

 period of from ten to eleven months, that is, on the coast of Massa- 

 chusetts, from the middle of July or the first of August to the middle 

 of the following June. The period of fosterage undoubtedly varies 

 considerably in eggs not produced in summer, some of which may 

 hatch in the fall and possibly in the winter months. 



Some lobsters become sexually mature when they are 8 inches 

 long, while a relatively small number do not produce eggs until they 

 have attained a length of 12 inches. The majority are mature when 

 IOY2 inches long. 



The law of survival of the larvae I have discussed in a paper 

 already referred to (Bulletin of the U. S. Fish Commission, Vol. 13. 

 1893). It is probable that the survival of 2 out of every 10,000 larvae 

 hatched, is a high estimate, since the female of average size produces 

 upward of 10,000 eggs at a single laying, and may have the opportunity 

 of reproducing more than once in the course of her life. The number 

 of survivals must be less than the number of adults caught and de- 

 stroyed each year, since the fishery is declining, and in some places 

 has been destroyed through the persistence with which it is carried on. 



Shortly after hatching her brood the mother lobster molts, but 

 does not produce eggs again until the following summer Very rarely 

 a female lobster molts just before extruding her eggs. In such cases 

 probably two molts intervene between the time of hatching of one 

 batch of eggs and the extrusion of another. 



Considering the fact that the American lobster ranges through 

 twenty degrees of latitude , from the southern coast of Labrador on 

 the north, to Delaware on the south, there is perhaps less variation in 

 the breeding habits than we should expect. In the north the eggs are 



