794 NATURAL HISTOEY OF AQUATIC ANIMALS. 



The following note regarding the shedding of the European Lobster, abstracted from a report 

 by a Danish naturalist, 1 goes to confirm our previous statement, that the females shed soon after 

 spawning : 



"After the Lobster has emitted its roe, and the young have left the mother, she begins to 

 shed. She therefore goes to safe places, and does not seem to care much for food while the old 

 skin is being loosened ; the shell finally opens in the back, and the animal goes into the water 

 naked. It then looks as if it were covered with velvet, on account of the considerable formation 

 of cells which is going on all over its surface. These cells afterward grow hard through small 

 particles of lime and form the new shell. This shedding of the shell goes on from the middle of 

 July to September, but not at the same time all along the coast, being earlier in the southern and 

 later in the northern part. The Lobster thus gets sick, as it is called, toward the end of June 

 near Sogndal, and the export must then cease, as the mortality among them becomes too great, 

 while near Karmo it is still in a healthy condition till July 15. Farther north the shedding of 

 the shell begins still later, and Lobster may be caught all through July." 



RATE OP GROWTH. Nothing is known regarding the rate of growth of the Lobster for any 

 extended period of time. Just how many years must elapse before it reaches a length of, say, ten 

 inches has never been determined, nor can we expect to solve this problem without a long series 

 of careful observations, which it seems almost impossible to make. It is well known that the 

 Lobster increases in size only when shedding. As the old shell is cast away the soft body rapidly 

 expands to a certain extent, and then soon becomes invested again with a new hard covering. 

 Knowing the frequency of the shedding periods, and the amount of expansion at each, we could 

 easily determine the age of Lobsters of all sizes; but these are the very data which are lacking. 

 It is probable that the rate of growth is not the same at all shedding periods, but is greater in the 

 younger stages than in the older. The early transformation from the embryo to the first perfect 

 lobster form are all accomplished during a single season by several moltings, but beyond this 

 period we know nothing accurately concerning the intervals between moltiugs, but in a medium- 

 sized Lobster they probably occur only once or twice a year. 



We have collected from several sources a few data as to the amount of expansion at certain 

 stages of growth, and although we cannot vouch for their accuracy, they are probably not far 

 from correct. The measurements given are for the length of the entire body without the claws. 

 One Lobster eight inches long before shedding measured ten inches after shedding; another 

 measured ten inches before and twelve inches after shedding; a third ten and one-half inches 

 before and eleven and three-fourths inches after shedding ; and a fourth ten and one-half inches 

 before and twelve inches after shedding. If these measurements had all been taken with care 

 they would indicate that the rate of growth was not always the same in different individuals of 

 about the same size. 



The lobster fishermen have very different notions regarding the ages of Lobsters, and while 

 some contend that they attain a marketable size in two or three years, others extend the period to 

 eight or ten years. The matter is one of considerable importance, bearing as it does upon the 

 framing of proper protective laws, and the feasibility of lobster culture and breeding. 



Mr. Frank Buckland, in his report for 1877, gives the two following notes on the frequency 

 of shedding and the rate of growth of the European Lobster. They are not, however, very 

 satisfactory; and we cannot believe that the American lobster sheds as frequently after the 

 first year or two. 



" According to some careful observations made at the marine laboratory, Concarneau, it 



1 AXEL BOECK: Om det norske Humrnerfiske og dets Historic. Copenhagen, 18G8-'69. 



