NATURAIv HISTORY OF AMERICAN LOBSTER. 187 



laboratory of its body, the lobster is able to transmute such products of organic decay 

 into the most delicate and palatable flesh. 



Lobsters are very fond of clams, as they are of moUusks of all kinds , and when 

 kept in pounds are constantly scoring and digging up the bottom in search for these 

 shellfish. In a large lobster pound at the Vinal Haven Islands I have seen the 

 muddy bottom scored in all directions, the work of lobsters in their search for clams. 

 One was reminded of a pasture in which the soil had been rooted up by pigs. As a 

 fisherman remarked, if you put lobsters in a pound and do not feed them they will 

 soon turn over the bottom as effectively as it could be done with a plow. Some of the 

 holes which the lobsters had made in digging clams were 2 feet in diameter and 6 inches 

 or more in depth. Here they had dug up the eel grass, or loosened it so that it had 

 floated to the surface, and cartloads had been cast ashore. We have already seen 

 that the lobsters sometimes eat parts of this plant, but they had plainly rooted it up 

 in this case with another object in view. The broken and often comminuted shells of 

 the long-necked clam {Mya arenaria) could be seen strewn everywhere about their 

 excavations. 



The lobster probably attacks such large and powerful mollusks as the conchs. 

 which live upon hard hnftnm in deep water, and devours their soft parts. An illus- 

 tration of this was afforded in an aquarium at Woods Hole in the summer of 1892, 

 when a conch (Sycotypus canaliculatus) was placed in the same tank with a female 

 lobster which was nearly 10 inches long and which had been in captivity about eight 

 weeks. The conch, which was of the av era ge size, was not molested for several days, 

 but at last, when hard pressed hv hunger, the lobster attacked it, broke off ito shell . 

 piece by piece, and made quick work of t he snff pieat 



If a lobster that has fasted for a number of hours is fed with a little fresh meat, 

 such as a piece of clam or fish, the process of feeding will be found to be one of no little 

 interest. The lobster eagerly seizes a piece of food with the chelae of the third and 

 fourth pairs of walking legs, and passes it up to the third pair of maxillipeds, which 

 are held close together, each being bent at the fifth joint and folded on itself. With 

 the third maxillipeds thus pressing against the mouth, the food is kept in contact with 

 the other mouth parts, all of which are in motion, and their action is thus brought to 

 bear upon it. By means of the cutting spines of the appendages external to the man- 

 dibles — chiefly the maxillae and second pairs of maxillipeds — the meat is as finely divided 

 as in a sausage machine, and a stream of fine particles is passed on toward the mouth, 

 to be finally subjected to the cutting and crushing action of the mandibles before 

 entering it. 



If one wishes to watch the movements of the complicated mouth parts more 

 closely, one has only to take a lobster out of the water, place the animal upon its back, 

 and when it has become sufficiently quiet stimulate the mandibles or the broad plates 

 of the second pair of maxillipeds with the juice of a clam or the vapor of ammonia, 

 which can be squirted with a pipette. Masticatory movements are immediately set up 

 in the appendages, those belonging to the side stimulated usually working independ- 



