August 1, 1899.] 



KNOWLEDGE. 



173 



that in many positions they try to look as if they weren't 

 there, or that they deliberately endeavour to wear an 



>>^l 





From Querin-Menev 





Parthenope horrida (Liiin.). 



unappetizing aspect, one may safely say that if they don't 

 try they often succeed without trying. In the fauna of Great 

 Britain and Ireland, we have some httle crabs, which may 

 be distinguished as Pennant's Ebalia, 

 Bryer's Ebalia, Cranch's Ebalia and Nor- 

 man's Ebalia, after the naturalists who either 

 acted as their publishing agents, or who first 

 brought their merits to light. These smaU 

 crabs love the deep waters. They are not 

 without some personal adornment, and there 

 may be a season of their lives when they will 

 run risks in order to display it, but in 

 general they find their advantage in resem- 

 bling little muddy rugged bits of stone. It 

 is from stony groimd that they are drawn to 

 the unwelcome light of day by the merciless 

 dredge or some exceptional storm. In cliffs 

 and quarries, we often please ourselves by 

 making out a human profile or perhaps 

 the figure of a couching lion. Niobe and 

 her children have been carved in the rock 



^y Tx without the aid 



of a sculptor. 

 There the acci- 

 dental and the 

 inorganic 

 mimic theforms 

 which we asso- 

 ciate with living 

 organisms. The 

 Great Warty 

 Crab (Parthe- 

 nope horrida) 

 makes an op- 

 posite appeal 

 to our inge- 

 nuity. It sets 

 though without the 



smallest desire that they should solve it — to find the living 

 crab in what looks like a casual fragment of rock. From 

 Guerin-Meneville's drawing, that might not seem to 

 be a difficult puzzle. There are, however, certain 

 points to be borne in mind. It was the artist's 

 business to show as clearly as possible all_ the 

 details of the organism. It is the crab's business 

 to conceal them. It cares not a whit whether we 

 can make out its specific characters, and would 

 bear without a murmur the calamity of being re- 

 ferred to a wrong genus. It gathers up its arms 

 and its legs into the smallest possible compass, in- 

 considerately making it quite difficult for any one 

 to observe the shape of its external maxillipeds, or 

 to see whether it has seven distinct joints in its tail 

 as a Parthenope ought to have. The tail itself, 

 usually so smooth a part in a crab, is here pitted 

 and eroded like a weathered piece of sandstone. As 

 for the tolerably symmetrical appearance, which 

 the drawing displays, and which properly belongs 

 to true crabs in general, no doubt a fish with an 

 aesthetic eye might consider the circumstance sus- 

 picious. But this crab, though unversed in the 

 biography of Sherlock Holmes, is not so weak as 

 to expose such a clue. It tosses on a rag of sea- 

 weed here and there, in a negligent manner, so as 

 to perfectly conceal the artfulness of its art. 

 OreSpliorus reticulatus of Adams and White, ae 

 may be seen from the picture, is a crab which 

 plays the same sort of game. 



Many crabs, and especially those of the tribe Oxyr- 

 rhyncha, indulge in a highly elaborate costuming, about 

 which much has been written of late. The improved and 

 multiplied aquaria of recent times have given opportunities 



Oreophorus reticulatus. From Adams and 

 White. 



its fellow-creatures the problem 





Lambrus cariiiatus Milne -Edwards. From Adams and White. 



for accurate observation of this strange procedure. It had, 

 indeed, been long ago recorded that several species, which 

 in youth had a smooth and shining carapace and legs but 

 slightly tomentose, assumed in age a very different appear- 

 ance. They seemed to become, as it were, " Half- suffocated 

 in the hoary fell, and many-winter'd fleece of throat and 

 chin," being all overgrown with the submarine fauna and 

 flora among which they lay. In their fakir-like existence, 

 they incurred the epithets of slow and sluggish, inert and 

 languid, inactive and apathetic. When Leach discovered 

 his Inachus dorhijnchm from the Salcombe Estuary, he 

 reasonably considered that this very circumstance of its 

 being generally overgrown with marine matter had con- 

 cealed it from earlier notice. Adams and White say of 

 Camposcia retusa, from the Philippine Islands, that "as it 

 advances in life, the carapace and legs become covered 

 with a thick, woolly, yellowish-brown tomentum, and, in 



