GG THE REPRODUCTION OF THE LOBSTER. 



warfare until one or the other has been killed. The loss of claws and 

 legs is of quite frequent occurrence ; and the fisherman, before confining 

 lobsters in a store-pot, invariably cuts the pincer muscles of the big 

 claws, in order to prevent them injuring each other. Even if no 

 instinct corresponding to maternal jealousy exists amongst these 

 animals, a female bearing eggs is placed at such a physical disadvantage, 

 that it is not unlikely that she would be more cautious of entering 

 a confined space with other lobsters. At any rate, this consideration 

 should be borne in mind when drawing conclusions from the results 

 arrived at by Ehrenbaum. 



An examination, made at the end of July, of the ovary of a female 

 whose brood had just been hatched, did not appear to me, in itself, to 

 ofTer evidence for or against the view that eggs would not be laid even 

 during the same summer. The ovaries were found to extend from the 

 anterior end of the cesophagus to the middle of the third segment of 

 the abdomen. The eggs were of a dark green colour, and in a lobster 

 30.5 cm. long, many of them had a diameter of as much as 1.2 mm. 

 If no further evidence of a different kind were forthcoming, one would, 

 I think, have been inclined to expect that these eggs would be laid 

 during the same summer. It seems to be very important for the settle- 

 ment of these questions that the rate of development of the eggs in the 

 ovaries of lobsters kept under conditions as normal as possible should 

 be determined, but this, of course, involves many dilliculties. It could, 

 probably, only be satisfactorily undertaken where the lobsters could 

 be confined in a large tidal pond from which they were unable to 

 escape but from which the water could at intervals be drawn off 

 completely. 



The number of eggs laid by a lobster becomes very much greater as 

 the age of the animal advances. This appears to be true, both of the 

 American and European species. A female 8 inches long, according to 

 Herrick, carries from 3,000 to 9,000 eggs, whilst in one measuring IG^^ 

 inches, the number was 85,000. As the result of an examination of 

 nearly a thousand individuals, this author finds that "the numbers of 

 eggs produced by a female lobster at each reproductive period vary in 

 geometrical series, while the lengths of the lobsters producing these 

 eggs vary in arithmetical series." 



Thus an American lobster 



8 inclies long produces 5,000 eggs. 

 10 „ „ „ 10,000 „ 



12 „ „ „ 20,000 „ 



U ,> » „ 40.000 „ 



11^ ,. » ,. 80,000 „ 



