LARVAL LOBSTERS 205 



than once. In this stage they are free-swimming Schizo- 

 pods about a third of an inch long, without appendages to 

 the pleon, but with six pairs of pediform appendages under 

 the carapace, each with an exopod developed into a power- 

 ful swimming organ. ' The eyes are bright blue ; the 

 anterior portion and the lower margin of the carapace and 

 the bases of the legs are speckled with orange ; the lower 

 margin, the whole of the penultimate, and the basal por- 

 tion of the ultimate segment of the abdomen [pleon], are 

 brilliant reddish orange.' In the second stage appendages 

 to the pleon have appeared on the segments from the 

 second to the fifth, these same segments carrying dorsal 

 spines as in the preceding and following stages, but with 

 successive reductions in their size. In the third stage the 

 appendages of the sixth segment of the pleon are well 

 developed, although quite different from those in the adult. 

 Considering that the Norway Lobster and the Common 

 Lobster when adult are so nearly allied that they might 

 almost be included in a single genus, the difference be- 

 tween the larval forms of the tw^o is at first sight rather 

 startling, but when more narrowly examined it will be 

 seen that the structure in both is essentially the same, 

 only that the telson of the larval Nephrops has been trans- 

 versely outdrawn to a portentous extent. The larval 

 Porcellana has been already mentioned as developing a 

 monstrous spine in the longitudinal direction ; the larvae 

 of the Cirripede, Lepas fascicular is, bristle with spines, 

 and it is likely that many of the infant Crustacea may 

 find in these processes an efficient protection to their 

 minute and delicate frames against foes not much bigger 

 than themselves. That they have such enemies it is easy 

 to guess, and Professor Smith says of his young lobsters 

 of the first stage, ' They appeared, while thus in confine- 

 ment, to feed principally upon very minute animals of 

 different kinds, but were several times seen to devour 

 small zoese, and occasionally when much crowded, so that 

 some of them became exhausted, they fed upon each other, 

 the stronger ones eating the weaker.' We cannot afford 

 to find fault with their juvenile morals, since similar prac- 



