72 BULLETIN OF THE UNITED STATES FISH COMMISSION. 



Table 21. — Percentage of male to female lobsters and the percentage of egg-bearing females taken in 



Woods Hole Harbor. 





Time of capture. 



For 

 w hole 

 period. 





1889, 

 Apr. 24 

 to 30. 



1889, 

 May. 



1889, 

 June. 



1893, 

 Dec. 



1894, 

 Jan. 



1894, 

 Feb. 



1894, 

 March. 



1894, 

 April. 



1894, 

 May. 



434 

 197 

 237 



1894, 

 June. 





104 

 49 

 55 

 49 



9J2 

 440 

 502 



2,184 



1,009 

 1,175 



224 

 123 

 101 



501 

 250 

 251 



246 

 116 

 130 



348 

 161 

 187 



457 

 247 

 210 



447 

 219 

 228 



5,887 



2,811 



3, 070 



49 



2, 529 



233 



55 



2,625 



396 



483 



2,593 



Males 



Males under 10 inches 





418 

 22 



976 

 33 



97 

 26 



215 

 35 



107 

 9 



137 

 24 



210 

 37 



173 



24 



196 

 23 



Males over 10 J inches 





Females under 10 inches 



55 



Females under 101- inches 



439 

 63 



185 

 317 



1,099 



76 



108 



1,067 



78 

 23 

 22 

 79 



194 

 57 

 30 



215 



106 

 24 

 11 



119 



147 

 40 

 12 



175 



163 

 47 

 33 



177 



207 

 30 

 34 



203 



192 

 36 



20 

 208 



Females over 10J inches 







22 

 33 



22 





Females under 10 inches with 



Females under 10£ inches with 



131 



54 



36 



19.6 

 114.3 



63 



45 



9 



4.9 

 116.4 

















Females over 10£ inches with 





















Percentage of females with eggs 

 to total number of females 



Percentage of females with eggs 

 to whole catch 



Percentage of females to males. . - 



40 



21 

 112.2 



21.78 



9.82 

 82.1 



14.34 



7.18 

 100.4 



8.46 



4.47 

 112. 07 



6.42 



3.45 

 116. 15 



15.71 



7.22 

 85.02 



14.35 



7.83 

 120. 30 



8.77 



4.47 

 104. 11 



17.48 



8.99 

 106. 30 



The inspector of fisheries for the Province of Prince Edward Island says: 



In 1879 returns from almost all the factories then in operation gave, for the whole catch, only 

 from 3 to 10 per cent in spawn, much the larger portion being in July. 



This agrees closely with the results obtained at Woods Hole, but it does not 

 follow, as Mr. Duvar supposes, "that one-fifth of the females carry ova each year," 

 or that "there are four times as many youug breeders coming forward as there are 

 egg-bearers," and "that one-fourth of the number come into breeding year after 

 year" (209, p. 234), since the adult lobster does not breed annually, as he erroneously 

 supposes. 



From December 1, 1893, to May 1, 1894, 358 female lobsters measuring 10 inches 

 or more in length were taken in the harbor of Woods Hole, and 1,234 were captured 

 during the same period at No Man's Land, in all 1,592 lobsters, 57 per cent of which 

 bore external eggs. If we include the 9-inch lobsters, we find that the total number 

 of females taken at both places is 1,779, and that 53 per cent carried eggs. This 

 supports the conclusion already reached from the study of anatomy, that the lobster 

 breeds once in two years, in which case 50 per cent, or fully one-half, of all sexually 

 mature female lobsters spawn in some part of each year. It also shows very forcibly 

 that valid inferences respecting the breeding habits can not be drawn from observa- 

 tions made in a restricted area. Thus, had our attention been confined to Woods 

 Hole it would have appeared that only one-fifth of adult females bore eggs (from 

 December to May), or that the lobster spawned only once in five years. ] 



1 Ehrenbaum (61) found that only 25.4 per cent of females supposed to be of adult age caught at 

 Heligoland carry eggs, and hence concluded that the European lobster becomes productive onlj once 

 in four years. Besides the objection that the data are derived from one locality, which, as table 21 

 shows, is a serious one, there is the further difficulty that over 10 per cent of these female lobsters 

 were captured during the months of July, August, and September, when, according to Ehrenbaum, 

 both the laying and the hatching of the eggs occur. This alone might vitiate the result. The best 

 way to test this question by experiment would be to take a female which had recently hatched a brood 

 and keep her alive until the following summer, when the next batch of eggs would be due, in case the 

 spawning period is a biennial one. So far as I know, this has never been done. 



