THE AMERICAN LOBSTER. 



51 



determined either (a) on the basis of the number of eggs to the grain, or (ft) by the weight 

 of 1,000 eggs. The numbers obtained by the last two methods agree very closely, and 

 it is plain that the dry method is the most reliable. The wet method gives a number 

 which is from 3 to 4 per cent greater than that obtained by the dry method. There 

 is probably a constant error of this amount in the wet method, 1 and this slight error is 

 due to the presence of the stalk of the secondary egg membrane, which has a tendency 

 to keep the wet eggs apart, but which shrivels and cracks oil' when dry. It increases 

 the buoyancy of the fresh eggs and is the cause of the bunching commonly observed. 

 The excess due to the bunching of the eggs is about 0.3 per cent. This source of error 

 was eliminated in No. 09 of the table, where the eggs were separated with needles 

 before measuring. 



THE LAW OF PRODUCTION. 



In table 15 I have reduced the results of a very large number of observations 

 made upon lobsters varying from 8 to 19 inches in length. The total number examined 

 is 4,045. Of these, 1,078 were taken on the ledges 1 5 miles southwest of No Man's Land 

 Island from April 20 to June 16, 1894. The remaining 2,967 were captured in Vineyard 

 Sound and in the vicinity of the Elizabeth Islands from April to June, 1889-94. A 

 smaller number were taken in February during the same years. The eggs went to 

 supply the hatchery of the United States Fish Commission. 



Tahle 15. — Production of eggs. 



Length of 



lobster. 



Smallest, 

 number 



Largest 

 number 



Average 

 number 



Number of 

 lobsters 



Length of 

 lobster. 



Smallest 

 number 



Largest 

 number 



Average 

 number 



Number of 

 lobsters 





oi eggs. 



of eggs. 



of eggs. 



examined. 



of eggs. 

 6,090 



of eggs. 



"f eggs. 



examined. 



8 inches 



3,045 



9,135 



4,822 



6 



13 inches 



48, 720 



28, 610 



321 



8^ inches 



6,090 



7.612 



6,851 



2 



13J inches 



24,360 



48, 720 



33, 495 



5 



8J inches 



3, 045 



12, 180 



6, 935 



9 



13i inches 



6,090 



54, 810 



32, 858 



146 





6,090 



9,135 



7,105 



3 



13J inches 



42, 630 



42, 630 



42, 630 



2 





3,045 



18, 270 



7,902 



143 



14 inches 



6, 090 



85, 260 



36, 960 



426 



9£ inches 



6.090 



12, 180 



9,083 



35 



14A inches 



21,315 



00, 900 



42, 968 



90 



9A inches 



3,045 



20, 792 



9,297 



241 



15 inches 



12,180 



97,440 



46, 524 



280 



9J inches 



10 inches 



3,045 

 3.045 



15, 225 

 24, 360 



9.947 

 10, 555 



55 

 514 









54, 810 



53,795 



1 



45 



15i inches 



24,360 



97,440 



lOJiuches 



6,090 



22, 838 



11.622 



61 



15|- inches 



48, 720 



54, 810 



50, 750 



3 



10A inches 



3,045 



36, 540 



12, 905 



532 



16 inches 



24, 360 



97, 440 



57, 146 



103 



10| inches 



6,090 

 3,045 



24, 360 



48, 720 



14, 067 

 15.410 



45 

 568 









66, 990 

 66, 053 



1 

 13 



16& inches 



36, 540 



85, 260 





6,090 



25, 882 



17, 102 



43 



17 inches 



12. ISO 



85, 200 



63, 336 



30 



lli inches 



3,045 



42, 630 



18, 668 



307 



17A inches 



60, 900 



73, 080 



64, 960 



3 





12, 180 



24, 360 



17, 993 



11 



18 inches 



60, 900 



91,350 



77, 430 



7 



12 inches 



3,045 



54, 810 



21, 351 



414 



19 inches 



54. 810 



91, 350 



77,647 



4 



12£ inches 



123 inches 



18, 270 

 9,135 

 18, 270 



27, 405 

 42, 630 

 .42. 630 



23, 396 

 24,812 

 26, 390 



8 



156 



12 



Total num 



her exami 



ned 







4,645 



i 







The average number of eggs of a lobster %f a given length has little value unless 

 obtained from a large number of individuals. While the small number of eags 

 occasionally recorded for lobsters over 12 inches long may be the result of loss, in 

 lobsters under this size it is probably, more often due to belated sexual maturity. 



1 This excess will probably about offset the slight loss of eggs which must always occur. The 

 numbers given in table 15 do not therefore require correction on this account. 



