28 OCEAN LIFE. 



servations do not, as far as we are aware, fully bear out the 

 above opinion of our ancestors as to the mode in which star- 

 fishes attack oysters, although the destruction which they cause 

 is pretty generally acknowledged. 



" The observations recorded by M. Eudes Deslongchamps upon 

 this subject are, however, exceedingly curious. As the waves 

 had receded from the shore, so as to leave only one or two 

 inches of water upon the sand, he saw numbers of Asterias 

 rubens rolling in bunches, five or six being fastened together 

 into a sort of ball by the interlacement of their rays. He ex- 

 amined a great number of such balls, and constantly found in 

 the centre a Bivalve Molluse, (Mactra Stultorum, Lin.) of an inch 

 and a half in length. The valves were invariably opened to the 

 extent of two or three lines, and the star-fishes were always 

 ranged with their mouths in contact with the edges of the valves. 

 On detaching them from the shell which they thus imprisoned, 

 he found that they had introduced between the valves large 

 rounded vesicles with very thin walls, and filled with a transpa- 

 rent fluid. Each Asterias had five of these vesicles ranged around 

 its mouth, but they were of very unequal size ; generally there 

 were two larger than the rest, equal in size to large filberts, 

 while the other three were not bigger than small peas. These 

 vesicles appeared to be attached to the Asterias by short pedicles, 

 and at the end of each was a round open aperture, through which 

 the fluid contained in the vesicle flowed out drop by drop. No 

 sooner was the animal detached from the shell that it was thus 

 sucking, than the vessels collapsed, and became no longer distin- 

 guishable. The Mactra were all found to be more or less de- 

 voured, some having only their adductor muscles left^ but, how- 

 ever little they had been injured, all had lost the power of closing 

 their valves and were apparently dead ; nevertheless there was 

 nothing to lead to the supposition that only dead shell fishes were 

 attacked, so that it is difficult to imagine how the delicate vesi- 

 cles above described escaped injury from the closing of the valves. 

 M. Deslongchamps thinks that probably the Asterias pours into 

 the shell a torpifying secretion, and thus ensures the death of 

 its victim." " The Asterias possesses no organs specially ap- 

 propriated to respiration ; but the sea water being freely admit- 



