412 REPORT OF THE COMMISSIONER OF FISHERIES. 
a lid, to expose the soft body beneath. Such a crab is termed a 
‘‘shedder” or a ‘‘ buster.” (Plate ur.) At this time the animal usually 
lies motionless, but if disturbed is still capable of movement, and may 
crawl or swim slowly away. It is incapable of showing any great 
muscular force, however, and can inflict only an insignificant pinch 
vith its claws. 
The actual casting of the shell is now a matter of only a few min- 
utes; a quarter of an hour will usually suffice, though the operation 
may be prolonged to three or four times that period if the crab is dis- 
turbed or if it issuffering from some recent injury. In the latter case 
it is often unable to complete the process and dies. By convulsive, 
throbbing movements the hinder pair of legs begin to be withdrawn 
from their encasement and are finally freed. . Meanwhile the other 
legs have been started out and the body has begun to protrude more 
and more from the shell. At last everything is out except the front 
of the body and the large claws, but the latter, on account of the great 
discrepancy between their size and that of the narrow articulations 
through which they must be withdrawn, require some-further effort 
before they can be freed. The thing would hardly be possible at all 
were it not for the fact that on the upper surface of the large segment 
of the arm (meros) a broad triangular surface of the shell becomes 
loosened and rises up like a flap to make way for the crowded tissues 
within. Some of the hard shell of the other lower (proximal) seg- 
ments also seems to become softened and elastic so that by a steady 
pull the great pincers are finally drawn through. Thus the crab has 
backed out of its shell and meanwhile it has grown, for if it is caught 
and measured it” will be found to be considerably larger than it was 
before.* (Plate rv.) 
The skin is soft and the animal looks and feels flabby and helpless. 
The back is wrinkled, and the ‘‘horns,” or large lateral spines, are 
curled curiously forward. Within a few minutes, however, the body 
mature. The specimens were taken from floats at Crisfield and were selected at 
random from among a large number. An effort was made to secure measurements 
of smaller individuals as well, but the lateness of the season made it impossible. 
Before | Before | 
shedding | ae shedding | rie 
totip | ding to tip ding 
across | =e across es 
the shell.) the shell. | 
Inehes. | Inches. Inches. | Inches. 
Meme Oy a) sseteecincnrcts cieidie see 4} | BE |, POMAle Secreciassticicwierejciereestaicte 4 | 43 
DOS ees saceee ees $i | 41 DOs deca Soto ceeen 4 5 
WO senmaecpsenaccee se aae 33 | 43 IDXo) SSaaonocOnGOSDoRccsSNs 3th oy 
DORs seco one ee no eee 4: 5} Maile: As er ec eias acide nceee ine 38 4} 
Does teria ee eee 4 4} | DO. o.oo eee 35 | 4h 
DO sso fovnictteisiamiele aus sinoereee 5} 63 | | 
| 
