362 MISS L. E, cnEESMAN : OBSERVATIONS ON 



Sense of Hearing. — No sign of response to any soiuul could be 

 obtained. During the expei'iment with flashlight mentioned 

 above, it seemed unlikely that the report of the concussion was 

 noticed ; it was the light alone which had a disturbing effect, 

 because two of the crabs were at an equal distance from the 

 light as that specimen which was being experimented iipon, but 

 the former were shaded from the glare by a piece of cork- 

 bark. The two which were exposed to the sound but not to the 

 light were carefully observed during the I'eports but made no 

 movement. 



Sense of Taste and Smell. — The seat of this sense must be inside 

 the mouth, possibly on the mandibular palp ; stones, morsels of 

 brick, and upon one occasion seaweed, were taken into the mouth, 

 and it wns fully two minutes before they were rejected as 

 inedible. The former could be heard distinctly to grate against 

 the mandibles. The antennules are not used in connexion with 

 food ; they are principally used when the crab is undei- water, 

 and may test the salinity of the water. 



Sense of Touch. — Setse are scattered over the limbs, and as the 

 crab moves sideways some of these are continually in contact 

 with the ground and reveal the nature of the surface nnd the 

 presence of food. Although the crab is undisturbed by any 

 vibration of the aii', there is immediate reaction to a vibration of 

 the ground. If a smart tap be given to the wooden partition 

 of the bay when the crabs have their backs against it, they will 

 respond to each tap by swinging the eyes into the sockets ; or 

 will move away as though alarmed. The tufts of setseat the base 

 of the claw of the first pair of walking legs are in constant 

 requisition while the crabs are feeding, to touch the food before 

 it is conveyed to the mouth. 



Further Observations on the Habits. 



Food. — Dead leaves and twigs form the main food of this species 

 in captivity. They also eat fresh fish and mice. They refvised 

 stale meat, but one night a mouse which had broken into the bay 

 was caught by a crab, and by morning was half devoured. They 

 were then supplied regularly with dead mice, and averaged about 

 one in every three days. After nearly eight weeks they refused 

 this diet and returned to vegetarianism, broken by an occasional 

 meal of fresh fish or an occasional mouse ; but they prefer all 

 flesh food very fresh. It was during this surfeit of mice that 

 their attitude of toleration towards one another was renounced 

 for combativeness, and five specimens died of injuries caused by 

 entire limbs being severed from the body. With the change of 

 diet this pugnacious mood subsided, and the chief aggressor now 

 lives peaceably with two smaller specimens. 



Method of Catching and Eating Mice. — The actual capture of a 

 live mouse has not been witnessed. When two live mice were 

 put into the bay one evening they showed a contemptuous 



