THE SHETLAND ARGUS. 



383 



taneously that even the most brittle species have no time to 

 make the contraction necessary to break off their rays. 



The Ophiocoma rosula seems to be equally abundant on all 

 parts of the coast of Britain and Ireland. It is fond of rocky 

 places, and grows in Shetland to a much larger size than else- 

 where. It is said to prey on little shells and crabs, and is 

 greatly relished by the cod in its turn, great numbers being 

 often found in the stomach of that voracious fish. 



The Scotch or Shetland Argus {Euryale verrucosum, La- 

 marck), a very rare animal, of which the adjoining wood-cut 

 represents a segment, is the only 

 British Euryale. It measures a foot 

 or more across, and its singular aspect 

 has long excited admiration among 

 naturalists. "So odd a creature as 

 this," remarks Bradley in his " Works 

 of Nature," "is well worth the con- 

 templation of such curious persons 

 as live near the sea, where every daj 7 

 they have subjects enow to employ 

 their curiosity and improve their 

 understanding." Grew says that 

 " as he swims he spreads and stretches 

 out all his branches to their full 

 length, and so soon as he perceives 



his prey within his reach, he hooks them all in, and so takes it 

 as it were in a net." 



The British species of true star-fishes may be arranged under 

 four families. The Urasters are distinguished from all others 

 by having four rows of suckers in each of the avenues which 

 groove the under surface of their rounded rays. In consequence 

 of the great number of these singular organs, the under surface 

 of a living cross-fish presents a sight truly curious and wonderful. 

 Hundreds of worm-like suckers, extending and contracting, 

 coiling and feeling about, each apparently acting independently 

 of the others, give the idea rather of an assemblage of polypi 

 than of essential parts of one animal. They are sensitive in 

 the extreme, for, if we touch one of those singular tubes when 

 outstretched, all those in its neighbourhood are thrown into a 

 state of agitation ; and when it shrinks from our touch, changing 



Warted Euryale. 



