NATURAI, HISTORY OF AMERICAN I^OBSTER. 

 THE SECOND I^ARVA. 



337 



[Fig. 41.] 



Under favorable conditions the first larval stage of the lobster lasts from i to 2 

 days. Upon molting for the first time after birth, the animal emerges into its second 

 larval, free swimming stage. 



Fig. 41. — Second larva, or second swimming stage of lobster in profile. For natural swimming position 

 hold page sidewise with head of animal down, and consult figure 40 of text . I^ength 9 m m ., or 0.3 5 inch. 



In habits and color the second larva resembles the first closely, but is distinguished 

 by its slightly larger size and by the presence under the tail of four pairs of swimmerets 

 on the second, third, fourth, and fifth abdominal segments, which appeared as minute 

 buds beneath the cuticle of the first larva at birth. These appendages lack the swim- 

 ming hairs, and do not become completely functional until the fourth stage. 



