STUDY ON THE HABITS OF THE CRAH. 165 



pulls the paper too strongly and the edge becomes torn farther 

 than necessary. But very rarely is the future case damaged in 

 this way, nearly always such tears are directed outwardly. It is 

 rather important to note that the animal does not pursue its 

 work along every cleft but it chooses the right direction, correcting 

 it every time. The clockwise direction of the work was just as 

 frequent as the opposite one. 



The legs of 2d-5th pairs participate indirectly in the work. 

 They hold the paper and present it to the chelae. If the crab 

 does not stop in its business, which occurs from time to time, the 

 process of cutting a case lasts about 15-30 minutes on the 

 average. 



The mode of working described is very frequently to be ob- 

 served; however, it is not the only one possible. Sometimes 

 before the cutting of the case is finished the crab grasps it with the 

 hooks of the 4th~5th legs and puts it on the back. The case 

 remains bound to the main mass of the paper. But after some 

 time the work is always completed. Still holding the paper on 

 the back Dromia may grasp the bridge, which joins the case with 

 the rest of the paper, and tear it. The easier way is to release 

 the case, to turn with the back towards the ground and to finish 

 the work in the same way in which it was begun. It sometimes 

 happens that the crab puts the whole paper on the back without 

 cutting the case. Then the edge of the paper lies at the level 

 of the forehead of the animal and the eyes remain uncovered. 

 Rarely Dromia enters under the paper, grasping it near the 

 middle. In both cases after some time the animal always starts 

 the work of cutting a case of suitable size. Ordinarily Dromia 

 releases the paper, turns on its back and begins to work as 

 described above. If the first tearing off of the paper occurs in 

 the middle of the whole piece, not at the edge, then Dromia folds 

 it twice with the chelae and tears it on the so-formed new edge. 

 If the paper bears a small hole the crab uses it as the starting 

 point of the work. Less frequent are the cases when Dromia 

 keeps its normal position, holding the paper on its back, and 

 without turning begins the cutting. The chelae tear off one little 

 piece of paper after the other, while the animal slowly revolves 

 under the paper, grasping it every time at a new spot. During 



