16 BULLETIN OF THE UNITED STATES FISH COMMISSION. 



esting facts in the life of the lobster, and to point out what seems to me the most 

 promising method of directing our energies in the work of its- artificial propagation.* 



The American lobster (Homarus americanus Milne-Edwards) is confined, in its 

 adult state, to a comparatively small strip of the Atlantic Ocean, stretching from 

 Delaware on the south to Labrador on the north, and extending in breadth from the 

 coast line out to a depth of 00 to 100 fathoms. 



The adult lobster lives and feeds exclusively upon the sea bottom, which it never 

 leaves of its own accord to any appreciable degree. It does not undertake periodic 

 littoral migrations up and down the coast, like the truly migratory fish, such as the 

 mackerel and cod, but is far more sedentary in its habits. In the spring, however, 

 about the first of May, when the temperature of the sea water approaches 55° F., it 

 begins to move from deeper water towards the shore, and in fall, about October, it 

 retires to deeper waters again when a similar temperature has been established; but 

 these semiannual impulses do not affect the entire number of lobsters in a given 

 locality, since some individuals remain in shallow water in winter and in deep water 

 in summer. Goode believes that the extensive northward and southward migrations of 

 the mackerel are carried on in connection with movements to and from deep water. 

 The same causes, of which the change of temperature is the most potent, probably 

 determine the migrations of both fish and crustacean. It is further possible that in 

 the case of the latter these short migrations are secondarily influenced by the occurrence 

 of the molting and reproductive periods. It is certain, at least, that in most cases the 

 eggs are laid and hatched while the lobster is in shallow water. 



As a rule lobsters are taken at a depth of from 1 to 10 or 12 fathoms, from the last 

 of April or first of May until October or November. During the rest of the year they 

 are mostly found in water of from 35 to 50 or 60 fathoms, and some stray out to even 

 greater depths. They seem to move back and forth more or less in a body, though it 

 is by no means certain that this is the case. 



The lobster must be regarded, as we have seen, as a relatively sedentary animal, 

 and the fact that it is steadily decreasing at most points on the coast, and that the 

 decrease is the most marked where the fishing has been conducted with greatest 

 persistence, points to the truth of this conclusion. The once famous Cape Cod fishery, 

 which dates back to the beginning of the century, and formerly supplied a large 

 proportion of the lobsters sent to New York City, is now practically extinct. The 

 region is depleted, and it will probably be many years before it can be restocked 

 under natural conditions. Indiscriminate and persistent fishing is certain to end in 

 the destruction of such a sedentary species as the lobster, and it is illogical, in the face 

 of an efficient cause for its decrease, to seek for other causes which are neither known 

 nor understood. 



The principal food of the lobster consists of fish, either living or dead, and of 

 clams and mollusks of various kinds. Fish which live upon the sea bottom, like 

 the flounder, doubtless fall a prey to their powerful claws, and I have known the lob- 



* The detailed work on the Life-History of the Lobster will probably be completed by the end of 

 the coming summer. It will contain a full presentation and discussion of all the facts that are known 

 concerning the habits and general life-history of the adult lobster, the habits of the larva-, and of the 

 young during their long period of immaturity, and the structure and development of the reproductive 

 organs. The development or metamorphosis of the larva', from the time of hatching, and their subse- 

 quent growth, will be fully described, and the development of the embryo will also be reviewed. The 

 paper will be illustrated with upwards of thirty-live plates. 



