290 



The true answer to the first question propounded above seems to 

 be as follows : The majority of adult lobsters extrude their eggs during 

 the months of June, July, and August, but a considerable number, 

 probably as great as ten per cent of the entire number which breed in 

 the year, lay eggs during the fall, winter, and spring months. Careful 

 systematic data have been collected by the U. S. Fish Commission 

 during the past winter at Woods Holl, bearing upon this and other 

 questions relating to the lobster, and will be given in the detailed 

 report now in the course of preparation. 



Newly laid eggs have been collected in the fall and winter on the 

 coasts of Maine and Massachusetts. Microscopical examination showed 

 them to be undergoing perfectly normal development from yolk-seg- 

 mentation onward. Mr. Vinai N. Edwards sent me a number of live 

 lobsters from Woods Holl, Dec. 4 th 1893. One of these had external 

 eggs, which had probably been extruded less than three weeks. At 

 Eastport, Me., a female lobster with partially discharged eggs was 

 taken from a lobster-car April 30th. , 1894 by Mr. W. J. Fisher. In 

 this case the eggs were laid in less than ten hours from the time the 

 lobster was placed in the car. About one eighth of the spawn was 

 under the »tail«; the rest was found in the body. 



This production of eggs outside of the summer months seems to 

 be a perfectly normal process, although a somewhat unusual one, and 

 it is possible that if the habits of many fish and other animals with 

 a fairly defijiite breeding season, were minutely studied, a similar 

 yariability would be found. 



How often does an adult female lobster breed ? It had been sup- 

 posed that the mature lobster laid eggs at least once a year. In the 

 paper already referred to I pointed out the important economic fact 

 that the adult lobster could not possibly breed oftener than once in 

 two years, that annual breeding was out of the question, as was 

 »abundantly proved by the slow growth of the ovarian eggs, by the 

 immature condition of the ovaries at the time when the young are 

 hatched, and by the large percentage of non egg-bearing females taken 

 in the winter and spring«. This fact was further established upon the 

 ground of anatomy by dissections and histological examinations of a 

 large number of individuals , representing every imj)ortant phase in 

 the growth of the ovaries. This is confirmed by Garraan (The Aqua- 

 rium, Jan. 1894. p. 91) who reaches conclusions similar to those 

 already expressed. 



The law of the production of ova may be expressed as follows : 

 the numbers of eggs produced by female lobsters at each reproductive 

 period vary in a geometrical series, while the lengths of the lobsters 



