APPENDIX. 97 



power of regeneration is the habit which the lobster has of throwing 

 off a claw, when it is crushed or injured (autotomy). 



7. SEXUAL MATURITY. 



Since it is impossible to tell how old a lobster is, we can not tell 

 at what age it reaches sexual maturity. Observation on several 

 thousand egg lobsters received at the experiment station during sev- 

 eral years seems to indicate that, in Narragansett Bay, lobsters may 

 become sexually mature when from 8{ to 9 inches long. In the past 

 ten years, only about twenty egg lobsters under 9 inches in length, 

 have been received, though a considerable number have been just 9 

 inches. This would indicate that in Narragansett Bay very few 

 lobsters under 9 inches have become sexually mature, although 9 

 inches is a good average. Herrick places the range in length of the 

 Massachusetts lobster, at the time of sexual maturity at from 8 to 

 12 inches, and thinks that 10 \ inches is the average length at sexual 

 maturity. 



8. SPAWNING HABITS. 



The female lobsters spawns once in two years. (Plate VIII.) The 

 eggs, as a rule, are laid in August, but some few lobsters lay them in 

 July and some later in the fall or winter. Hatching occurs the 

 following summer at a time determined by the temperature of the 

 water to which the eggs have been subjected during the period in 

 which they have been carried. In Narragansett Bay it usually takes 

 place from the first of May to the end of July. 



The lobster therefore carries its eggs for a period of 10 or 11 months 

 before they hatch. The number of eggs carried by a lobster varies 

 according to the size of the lobster; thus, according to Herrick, assum- 

 ing that an 8-inch lobster has on the average, 5,000 eggs, a 10-inch 

 lobster would have 10,000, a 12-inch lobster, 20,000, etc. A lobster 

 about 16 inches long would thus lay about 80,000 eggs. This is, 

 however, a low average. Lobsters 16 inches in length, may have 



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