58 BULLETIN OF THE UNITED STATES FISH COMMISSION. 



The last lobsters with light eggs were taken by the Gay Head lobsteriiien iii 1890, 

 July 7. This was also the date of the capture, at that point, of the first lobster with 

 new eggs. 



The time occupied by the hatching of a single brood was upward of a week, in 

 the following case: On June 30, 1891, a lobster with old eggs, taken in Woods Hole 

 Harbor, was stripped, and the spawn was placed in a " McDonald " jar. On July 3 one 

 larva had appeared; by July 5 a dozen larvae had been hatched; on the 13th of the 

 month hatching was still progressing slowly, and some of the young had molted and 

 were in the second stage. 



In another lobster taken at Menemsha, July 11, 1891, with young just hatching 

 out, the eggs, treated in the same way, were nearly all hatched in one week's time. 

 On July 12 a large number of the first larvae were swimming about the jar, and on 

 July 18 the eggs were mostly hatched and many of the young were in the second 

 larval stage. 



In July and August, 1892, Mr. A. P. Greenleaf placed 300 egg-lobsters from Nova 

 Scotia with newly laid eggs in one of the lobster pounds at Southport, Maine. In 

 April, 1893, he seined, and found the females stdl bearing eggs. He seined the pond 

 again in June, when it was evident that the larger part of the eggs had hatched. 



Mr. Thomas Garrett, who began to fish for lobsters in the Vinal Haven Islands 

 over forty years ago, caught in July a large, old egg-lobster, which weighed about 

 pounds, in the " Basin" near the present lobster park. He returned it to the water, 

 caught it a second time, liberated it again, and about the 1st of August caught it for 

 the third time, when the eggs had all hatched out 



THE DISPERSAL OF THE YOUNG. 



With the hatching of the young the period of fosterage comes to an end. 1 By the 

 fanning movements of her swimmerets the young are driven away from the body of 

 the mother as soon as the egg-membranes have burst and are immediately dispersed ; 

 thenceforth they lead a free and independent existence. 



The hatching of the eggs of the lobster has been often witnessed by smackmen 

 and keepers of lobster pounds. In May, June, and July "the surface of the water in 

 the wells of the smacks often becomes perfectly alive with the young, and they may be 



Nothing very definite seems to be known about the ovulation and hatching of the young in 

 the European lobster, Astacus gammarus. Rathke's observations in 1840 did not settle the question 

 (see p. 167), and Sars's paper {175), published over thirty years later, left it still in doubt. Sars 

 says that "the reproduction of the lobster does not appear, as is generally held, to be confined to any 

 definite period of the year, yet the youug are mostly hatched in summer. It is not unusual, however, 

 to find the lobster with external eggs at other times of the year." Mayer (138) remarks that there is no 

 definite breeding season, but that Homarus (Astacus gammarus) and Palinurus extrude their eggs mostly 

 in November and December. These conflicting statements show that the European lobster carries her 

 external eggs for a long period, and I have no doubt that when this subject is carefully investigated 

 it will be found that the breeding habits of Astacus gammarus are very similar to those of the American 

 species. 



When this work was in press and after the preceding note was written I received Dr. Ehren- 

 baum's paper, to which I have already referred (61). He says that the eggs are laid and the young 

 are hatched from about the middle of July to the middle of September. In one of two cases observed 

 the eggs were laid August 1, 1893, and the first larva? hatched July 20, 1894; in the other, the eggs 

 were extruded August 28, 1893, and the larva} hatched July 21, 1894. The period of incubation is thus 

 about 11 months, as in the American form, and the times of the laying and hatching of the eggs in the 

 two species very nearly agree. 



