THE CRUSTACEA 127 



by everything in the sea which has a month). They are 

 very voracious little things, and attack animals larger 

 than themselves. They are also inclined to cannibalism. 



Then, when about an inch long, they take to bottom, 

 and have the form and habits of the parent, hiding in rock 

 crevices and under stones. The first year the shell is cast 

 several times, as growth advances. Then for three or 

 four years once a year, less frequently after that. The full 

 size is attained when they are from five to seven years old. 

 A specimen which has reached size-limit can be easily 

 recognised by its having the claws and walking feet abraded 

 and worn, and having barnacles and serpulae attached to 

 the shell, showing that it has not been lately renewed. 

 The shell-casting, or " Ecdysis," as it is termed, is a very 

 interesting process, and will be referred to in the section 

 on the Brachyura. 



The lobster affords a considerable fishery, both at home 

 and abroad. It is mostly taken here in baited wicker 

 traps, called " lobster pots " ; in the big fisheries of New- 

 foundland, etc., in cages made of wooden laths, about five 

 feet long by three feet high and three feet wide, with two 

 " free admittance no exit " openings at each end. (The 

 wicker " pots " have but one, this at the top.) 



The lobster, where numerous in shallow waters, is also 

 lured from its hiding and speared. 



On all rocky shores specimens may be taken in rock 

 crannies and under boulders, in the lower part of the 

 littoral. 



(The anatomy of the lobster is extremely interesting, and 

 the young naturalist will do well to study it Huxley's 

 classical work, " The Crayfish," for his guide.) 



The nearest ally to the lobster is the fresh- water " cray- 

 fish," but in marine forms its allies are not very familiar 

 to most persons, although they are fairly common. 



The first of these is Axius stirhynchus. This is very like 



