A NATURALIST. 85 



possible to refer to nature for the actual condition 

 of facts, learned authorities give me no uneasiness. 

 If I find that the structure bears out their opinions, 

 it is more satisfactory; when it convicts them of 

 absurdity, it saves much fruitless reading, as well as 

 the trouble of shaking off prejudices. 



The first time my attention was called to the 

 extreme acuteness of sight possessed by these ani- 

 mals, was during a walk along the flats of Long 

 Island, reaching towards Governor's Island, in New 

 York. A vast number of the small land-crabs, 

 called fiddlers by the boys (gecarcinus), occupy 

 burrows or caves dug in the marshy soil, whence 

 they come out and go for some distance, either 

 in search of food or to sun themselves. Long 

 before I approached close enough to see their forms 

 with distinctness, they were scampering towards 

 their holes, into which they plunged with a toler- 

 able certainty of escape these retreats being of 

 considerable depth, and often communicating with 

 each other, as well as nearly filled with water. On 

 endeavouring cautiously to approach some others, 

 it was quite amusing to observe their vigilance to 

 see them slowly change position, and, from lying 

 extended in the sun, beginning to gather them- 

 selves up for a start, should it prove necessary: at 

 length standing up, as it were, on tiptoe, and raising 

 tjieir pedunculated eyes as high as possible. One 

 quick step on the part of the individual approaching 

 was enough away they would go, with a celerity 

 which must appear surprising to any one who had 



