76 BULLETIN OF THE UNITED STATES FISH COMMISSION. 



process have been studied by Max Braun (22), and more recently by Vitzou (197). As 

 so often bappens, there are many observations on this subject which either ignore the 

 earlier and often better ones, or add nothing of value to our knowledge of the process. 

 Hyatt, in remarking that, while the molting of the lobster had been previously de- 

 scribed several times, "do professional naturalist" had "actually seen the process and 

 recorded his observations," appears to have overlooked the account of Sars (176), which, 

 however, is not particularly circumstantial. 



Sars saw a lobster in the act of molting in July near Tananger, in Norway. He 

 says : 



It had just been taken out of a lobster box, and could be handled without its offering the slight- 

 est resistance. The shell on its back was burst in the middle, and the tail and the feet were nearly out of 

 the old shell, while the largest claw stuck out only half its length. This latter portion of the change is 

 evidently very dangerous, and, although I observed it for quite awhile, I could see little or no progress. 



This lobster was not a good exponent of the molting process. As soon as the 

 larger claws begin to be withdrawn from the old shell the exuviation, under normal 

 conditions, is speedily brought to a close. Nor is it true that the lobster " only reaches 

 its former size after a considerable time has elapsed." According to Sars, the lobster 

 on the Norwegian coast molts chiefly in July. 



Both Couch (45) and Salter (174) have given accounts, at secondhand, of the 

 molting of the European lobster. Couch, writing in 1837, says that the newly molted 

 lobster shows great activity in effecting its escape, which is undoubtedly true in some 

 cases, but not in all. The lobster whose cast shell is described escaped "through an 

 aperture too narrow to have allowed it to pass if its new covering had possessed a 

 very moderate degree of firmness." He supposed that escape was effected by the 

 cracking open of the shell, in the middle line, where he noticed that in life a faint 

 stripe was perceptible. He observed in a lobster prepariug to molt that absorption 

 took place along this area, and inferred that the two halves of the shell were com- 

 pletely separated when the critical moment came. Of the molting, he further says that 

 " it is not improbable that the general opinion is correct which limits the exuviation of 

 the adult animals to once in the year," and " general opinion" does not seem to have 

 made much progress in clearing up this matter during the last fifty years. 



Salter's account, published in 1860, is interesting on account of some extraordi- 

 nary statements, such as that in molting the legs are extracted pair by pair, which of 

 course is a physical impossibility, as Hyatt pointed out, and that the abdomen is the 

 part first withdrawn from the old shell. This latter statement expresses exactly the 

 reverse of what has since been found to occur. 



Wheildon (202) published in 1875 a short paper containing some interesting facts 

 on the molting habits of the American lobster, which will be referred to again. 



The work of Vitzou, which appeared in 1882, is the best yet done on this subject. 

 He treats of the histology of the old and new shell, and of the organic and "inorganic 

 reserves," which are supposed to be laid down in certain tissues with reference to the 

 molting period. 



Hyatt's paper (104), appearing in 18S3, gave an accurate account of some of the 

 phenomena of exuviation in this species. 



Packard in 1886 published some notes (147) in which very little is added to our 

 knowledge of the subject. He says that "the integument of the legs is molted last, 

 and when, owing to rough handling, the process is delayed, the extremities of the legs 



