THE AMERICAN LOBSTER. 



55 



eggs; 15 per cent carried from 15,000 to 16,000; 6 per cent had 18,000 to 19,000; one 

 individual carried upward of 21,000, while 4.0 per cent bore only 3,000 to -1,000. This 

 is further illustrated by cut 3, which shows the variation in fecundity of 352 lobsters 

 each 10 inches long. In this case 20 per cent laid 9,000 eggs, 30 percent 12,000, not quite 

 1 per cent 18,000. The curve drops and keeps well down after the 12,000 limit is 

 reached, which possibly implies a loss of eggs in those lobsters having more than the 



average number. 



Table 16. — Production of eggs by volume. 



Length 

 of lobster. 



8 inches 

 8^ inches 

 8J inches 

 8J inches 



9 inches 

 9J inches 

 9A inches 

 9| inches 



10 inches 

 10.} inches 

 lOt inches 

 lOf inches 



11 inches 

 11 J inches 

 11J inches 

 11"; inches 



12 inches 

 124, inches 

 12. V inches 

 122- inches 



Smallest Largest 



number | number 



of 11 aid j of tin id 



ounces, ounces. 



Average 

 number 

 of fluid 

 ounces. 



.78 

 1.12 

 1.14 

 1.17 

 1.30 

 1.50 

 1.53 

 1.63 

 1.73 

 1.91 

 2.12 

 2.31 

 2.53 

 2.79 

 3.06 

 2.95 



Number 

 of lobsters 

 examined. 



6 



2 



9 



3 



143 



35 



241 



55 



514 



61 



532 



45 



568 



43 



307 



11 



414 



8 



156 



12 



Length 

 of lobster. 



13 inches. 

 13 J inches. 

 13.;, inches. 

 13^ inches. 



14 inches. 

 14i inches. 

 15" inches . 

 15 J inches. 

 15J inches- 

 15! inches. 



16 inches. 

 164, inches, 

 ltii inches. 



17 inches. 

 17A inches. 

 18" inches - 

 19 inches. 



Smallest 

 number 

 of fluid 



ounces. 



6 

 2 



10 



10 



Largest 

 number 

 of fluid 

 ounces. 



Total number examined. 



Average 

 number 

 of fluid 

 ounces. 



4.70 

 5.50 

 5.39 

 7.00 

 6.07 

 7.05 

 7.64 

 9.00 

 8.83 

 8.41 

 9.38 

 11.00 

 10.85 

 10.40 

 10.67 

 12.71 

 12.75 



Number 

 of lobsters 

 examined. 



321 



5 



140 



2 



426 



90 



280 



1 



45 



3 



103 



1 



13 



30 



3 



7 



4 



4,645 



The data collected in table 16 will show in still another way the variation in the 

 quantity of eggs produced by lobsters of different sizes. The average weight of a 

 lOi-inch female lobster with eggs is If pounds (table 31), the eggs weighing about 

 2 ounces. A 15-inch lobster which weighs upward of 4 pounds (table 31), sometimes 

 carries a burden of a pound of eggs. As already remarked, a fluid ounce of fresh 

 eggs weighs about 1 ounce avoirdupois. 



PERIOD OF INCUBATION AT WOODS HOLE AND RATE OF DEVELOPMENT. 



The freshly laid eggs are somewhat irregular in shape, but soon plump out and 

 become nearly spherical. Some, however, have the form of elongated spheroids (plate 

 17, fig. 24). They measure approximately -^ inch in diameter, or 1.5 to 1.7 mm. In 

 color they are dark olive-green, 1 sometimes almost black, hence the use of the term 

 "black egg-lobster," common among fishermen, to distinguish the "new egg- lobster" 

 from the "old" or the "light egg-lobster," in which the dark-green food yolk has 

 been more or less absorbed by the growing embryo. In England the female lobster 

 with external eggs is spoken of as being "in berry," or is sometimes called a "berried 

 hen." 



The rate of development of the summer eggs at Woods Hole is illustrated by 

 tables 17 and 18, and by cuts 23-38 (plates G to J). 



1 For variation in the color of the egg, see p. 137, and plate 17, rigs. 23 and 24. 



