21 8 BUMPUS. [Vol. V. 



lected during the winter months, both from the colder waters 

 of Nahant as well as from the warmer waters of Wood's Holl, 

 were almost invariably in the same advanced stage of devel- 

 opment — the eyes large and bright, the appendages well out- 

 lined, and the yolk occupying but a fraction, perhaps one-third, 

 of the surface exposure. 



I was not surprised, therefore, on continuing work at the 

 United States Fish Commission Laboratory at Wood's Holl, early 

 in May, 1890, to find that of hundreds of lobsters then "in 

 berry," not a single one had eggs in early stages of development. 

 Millions of eggs were kept alive in "Chester" and "McDon- 

 ald " jars, but not an egg hatched until May 14, when the water 

 had reached a temperature of 52 F. From then until the water 

 reached a temperature of 70 the young actually swarmed in the 

 hatchery. 



The hatching period extends, then, from the middle of May 

 to the middle of July, after which time only a few mature eggs 

 are to be found. 



The eggs are normally carried by the female from nine to ten 

 months. 



While the work of hatching was in progress it occurred to me 

 that artificially raising the temperature of the water might yield 

 interesting results, and certain experiments convinced me that 

 the eggs might be taken from the female at any time during 

 the winter or spring months, and after a few days of "artificial 

 incubation " hatch and give rise to perfectly healthy young. 



The above suggests a possible(?) solution of the problem of 

 successfully rearing the young. For if the artificially hatched 

 larvae were again placed in the colder water of the ocean, they 

 would certainly escape the attacks of many summer enemies. 

 That the change from warmer to colder water would not prove 

 immediately fatal is demonstrated by the fact that a prolonged 

 immersion in water at 33 F. produced no visible harm to the 

 young lobsters. 



Though thousands of female lobsters were examined during 

 the month of June, not a single fresh-laid egg could be found. 

 It was not until July that they made their appearance, and 

 not until the latter part of that month that they were at all 

 abundant. 



Whether the female lobsters which have just hatched their 



