The Lobster. 65 



are the pair of mandibles or chewing jaws. Let us put 

 ouv probes between tbe mandibles into the mouth. 

 These six pairs of appendages are called mouth-parts. 

 What other appendages has the lobster ? 



He has two pairs of feelers. Those are his antennae. 



What is curious about his eyes ? 



They stick out from his head, and can be moved about. 



The eyestalks are another pair of appendages. How 

 many pairs of appendages are there on the head-thorax ? 



There are fourteen pairs. 



How many pairs on the abdomen ? 



There are six pairs. 



Now we will compare the legs. How many joints 

 have they ? 



The big legs have six joints and the others have seven. 

 The joints move in different ways. The first pair of legs 

 end in large claws, the next two pairs in small claws, and 

 the last two pairs in sharp points. One great claw has 

 broad, blunt teeth, the other has sharp teeth. 



Since the lobster lives in shallow water, he uses his four 

 pairs of small legs in walking over the rocky bottom. The 

 great claws are kept for fighting and tearing his prey. If 

 he loses one in a duel, another soon takes its place. While 

 the broad teeth on one ciaw often anchor the lobster to 

 some large seaweed, or are used as millstones for crushing 

 his food, the other claw catches fish and tears them apart 

 with its sharp teeth. 



While the great olawa capture moving prey, the third pair of 

 iaw-feet pick np food from the bottom, and their aaw-like inner 

 edges help to tear it in pieces. The other month-parts, especially 

 the strong mandibles, do the rest of the work of biting and shew- 

 ing, though the little jawa seem too soft to be of mnoh nse. 



We notice that the first pair of antennae (Fig. 1, a',) 

 are very short and have two parts, but the second pair 

 (a') are very long and made of many little joints. 



