338 REPORT OF NEW JERSEY STATE MUSEUM. 



the fourth pair of legs. Males do not discriminate the 

 sexual condition of the female, which may be impregnated 

 any time. Probably copulation takes place usually in the spring. 

 Most females lay eggs in July and August, though eggs are 

 also laid in lesser degree at other times. The females 

 carry the eggs from ten to eleven months. Summer spawn- 

 ing- lasts about six weeks. A lobster about eigiit inches long 

 will produce 5,000 eggs, while one seventeen inches pro- 

 duces about 63,000. The egg-bearing female moves about with 

 the tail folded. The period of hatching of a single brood lasts 

 sometimes over a week, owing- to the unequal development of 

 the eggs. Females are sexually mature when from eight to ten 

 inches long. Spawning does not take place more than once in 

 two years. The relative number of males and females varies 

 considerably in certain localities. Moulting takes place mostly 

 during June till September, but soft ones are found at all times 

 of the year. Males probably moult more frecjuently than the 

 females, thus accounting for the large proportion of soft ones 

 and the greater size attained. Moulting lobsters are more often 

 taken on sandy or weedy than on rocky bottoms. From six to 

 eight weeks are necessary to produce a shell as hard as the one 

 cast off. Growth \'aries considerably with indi^•iduals and sur- 

 roundings. When hatched a }-oung loDster is 7.84 mm. long, 

 and it then moults from fourteen to seventeen times during the 

 first year. A ten and one-half inch lobster has moulted twenty- 

 five or six times and is about five years old. All the appendages 

 are capable of regeneration, and defensive mutilation is per- 

 fectly developed only in the large chelipeds. The greatest size 

 attained ]yy lobsters is about twenty-five pounds. Every pre- 

 daceous fish which feeds on the bottom may be an enemy and the 

 cod is one of the most destructive to small lobsters after the 

 larv^al stages are passed. 



Color variations, like the red, blue and cream colored types, 

 are nonadaptive, and this is true of the remarkable color varia- 

 tions in the larv?e and older stages. The normal color has, 

 however, a protective significance. The large crushing claw 

 may be either on the right or left side, and it is probable that 



