1880 .] 
85 
[Hyatt. 
These observations were made upon an animal living under 
unnatural conditions and therefore have a certain doubt attached 
to them. The manner of withdrawing the abdomen first and then 
the legs of the cephalothorax, leaving the great claws last would 
seem to be an exceedingly awkward operation since it does away 
with all the advantages of a natural base for operations furnished 
by the abdomen when this remains fixed ; this is also contrary to 
the observed mode of operation in the Cray-fish. The extraction 
of the legs pair by pair as described by Salter is an impossibility. 
One pair of legs cannot be drawn out without at the same time 
drawing out the next pair to a proportional distance. Neverthe- 
less Salter’s observers reported that each pair of walking legs, 
beginning posteriorly, were drawn out separately. 
Mr. John Silsbee observed the moulting in one case which is 
reported by Dr. A. S. Packard, Amer. Nat. Yol. 8, p. 417. The 
shell and the animal were brought to Dr. Packard immediately 
after moulting and the animal was reported by Mr. Silsbee to 
have cast off the old shell through a split along the median line 
of the carapax. The shell as seen by Dr. Packard confirms these 
observations. The animal when seen by Dr. Packard was three- 
quarters of an inch longer than the shell, and the claws soft and 
watery. 
Mr. S. M. Johnson of Boston discovered an important and alto- 
gether new fact in the process of exuviation, which is recorded by 
W. W. Wheildon in Proc. American Ass. Adv. Science, Aug., 
1874, p. 139. This is the absorption of the shell on the inner side 
of the great claws, at the base of the legs, which explains how it 
is that the flesh of these parts can be easily extracted, as in the 
case recorded below. 
My own observations were made upon one specimen which I 
had an opportunity of seeing at the island of Matinicus, while 
on a cruise along the coast of Maine during the past summer. 
Mr. A. Condon hailed our yacht, the Arethusa, while at anchor in 
the harbor, with extraordinary vehemence one morning, inviting 
us to come and see a lobster joassing through the critical operation 
of moulting. When we arrived, the animal was lying on his side in 
a fish tub, and drawing out the large claws, the walking legs and 
whole forward part of the body. The operation was being per- 
