FLIES CRABS 231 



preserver Laving invited a friend to dine and sleep at his house, 

 the fly, the next morning, perched upon the thumb of the 

 visitor, who, being ignorant that it was a pet of his host's, 

 clapped his hand upon it, and thus put an end to Mr. Slingsby's 

 experiment. 1 



Crustacea. 



There is no doubt that these are an intelligent group 

 of animals, although I have been able to collect but 

 wonderfully little information upon the subject. Mr. 

 Moseley, F.R.S., in his very interesting work, ' Notes by a 

 Naturalist on the Challenger ',' says (p. 70) : 



In the tropics one becomes accustomed to watch the habits 

 of various species of crabs, which there live so commonly an 

 aerial life. The more I have seen of them, the more have I been 

 astonished at their sagacity. 



And again (pp. 48-9) : 



A rock crab (Grapsus stringosus) was very abundant, run- 

 ning about all over the rocks, and making off into clefts on one's 

 approach. I was astonished at the keen and long sight of this 

 crab. I noticed some made off at full speed to their hiding- 

 places at the instant that my head showed above a rock fifty 

 yards distant. . . . 



At Still Bay, on the sandy beach of which a heavy surf was 

 bi-eaking, I encountered a sand crab (CEcypoda ippeus), which 

 was walking about, and got between it and its hole in the dry 

 sand above the beach. The crab was a large one, at least three 

 inches in breadth of its carapace. . . . With its curious column- 

 like eyes erect, the crab bolted down towards the surf as the 

 only escape, and as it saw a great wave rushing up the shelving 

 shore, dug itself tight into the sand, and held on to prevent the 

 undertide from carrying it into the sea. As soon as the wave 

 had retreated, it made off full speed for the shore. I gave 

 chase, and whenever a wave approached, the crab repeated the 

 manoeuvre. I once touched it with my hand whilst it was 

 buried and blinded by the sandy water, but the surf compelled 

 me to retreat, and I could not snatch hold of it for fear of its 

 powerful claws. At last I chased it, hard pressed, into the 

 surf in a hurry, and being unable to get proper hold in time, it 

 was washed into the sea. The crab evidently dreaded going 

 into the sea. . . . They soon die when kept a short time be- 

 xieath the water. 



1 Gleanings, vol. ii., pp. 165-6. 



