SPIDER-CRABS 311 



Referring to spiders reminds me that there are at 

 least five species of spider-crabs on the reef, the largest of 

 which, with a body no larger than a cocoa-nut, has legs 

 which will span a radius of seven feet. This is quite a 

 distinct species from the large crab mentioned as haunting 

 the Abrolhos reef. None of the five members of the 

 Oxyrhyncha family referred to here seem to be figured in 

 classified lists. One much resembles Macropodia longir- 

 ostris, but with a shorter beak and more rounded body, 

 and is, moreover, twice the size of that species. It may 

 possibly be the larva of some other crustacean ; and the 

 same may be said of one other species. 



It was found to be impossible to obtain a perfect 

 specimen of the large crab mentioned above. The animal 

 ensconced itself in the midst of intricately branched masses 

 of coral, where it could not be reached by the hand; and 

 if a leg was seized, it at once threw off the whole or part 

 of the member, while the animal itself quickly sank into 

 the depths beneath it. 



Many hundred species of crustaceans live on and about 

 the reef, most of which are very small. Crabs of the size 

 of a sixpence, and of a purplish or violet colour, are very 

 abundant. Others the size of a penny-piece are a bright 

 yellow ; and some species are noticeable for eccentricity of 

 form. The singular enlargement of one claw or nipper, 

 so frequently seen in the land crabs, is very prevalent 

 amongst the Barrier Reef crustaceans. There is a species 

 of shrimp or prawn on the outer face of the reef where the 

 water is deep which has this peculiarity, and several of 

 the crabs are noticeable for a like singularity. 



Among the lower forms of animal life, nearly every 

 family of insect and arachnida is imitated in shape by some 

 species of crustacean ; and on the reef may be found what 

 may justly be termed ocean spiders, millipedes, scorpions, 

 and creeping and crawling things innumerable, leaving a 

 strong impression on the mind that every terrestrial 

 animal has its counterpart in the ocean, however widely 

 it differs in some one or more essential part. Evolution 

 admitted, surely the crabs are highly specialised spiders 



