110 TRANSACTIONS LIVERPOOL BIOLOGJCAL SOCIETY. 



towards tlie end of the summer of 1901. These eggs 

 commenced hatching early in August, 1902, and by the 

 end of that month had all hatched. After an interval of 

 less than six weeks, during 1 which there was no possible 

 chance of the shell being cast and escaping observation, 

 another batch of eggs was extruded, without any interven- 

 ing moult. That is, this lobster has definitely produced 

 one batch of eggs each year, for two successive years, with- 

 out moulting. Of the batch of five lobsters referred to at 

 the beginning of this article, two moulted very soon after 

 their eggs hatched and have produced no other eggs, two 

 produced eggs without moulting, but only one was actually 

 observed in the act, and the remaining one has done 

 nothing. 



Dr. li. C. Williamson in his valuable paper " Contribu- 

 tions to the life history of the edible crab,"* - gives impor- 

 tant information on the spawning and moulting of that 

 crustacean, and also a summary of the opinions held by 

 various zoologists on the same process in the lobster. 



Dr. Williamson states : " A crab does not always cast 

 immediately it hatches its eggs. It very often carries 

 eggs two years in succession." And again the crab " Will 

 keep on having successive batches of eggs until the supply 

 of sperms is exhausted." 



llerrick in his summary of observations on the 

 American lobster (p. 222), states : " The lobster does not 

 spawn often er than once in two years. The spawning 

 period is probably a biennial one, one set of eggs (summer 

 eggs) being laid in July or August (at Woods IloJl), and 

 the following set in two years from that time. One has 

 only to examine the ovary of a lobster which has just 

 hatched a brood that is one year from the time of last 



* Eighteenth Annual Report . Fishery Board for Scotland, Part III. 



