THE OPELET. 165 



by their own weight. At other times it rises to the very 

 water's edge, and even thrusts out its base in an inverted 

 position upon the surface of the water, as if it would float 

 by the mere contact of the dry base with the air, just as the 

 Limnecc and many other Mollusca do. And not seldom 

 does it boldly break the tie that connects it with the side 

 of the vessel, and actually swim, or at least passively float, 

 with its base in contact with the inferior surface of the 

 superincumbent stratum of air. A little shaking of the 

 vessel, however, causes the water to overflow the frail boat, 

 which had been hitherto dry, when the animal instantly 

 falls prone to the bottom. 



No very special care is required to maintain the health 

 and vigour of the Opelet in captivity : as to situation, it 

 will select for itself the position its wayward will may most 

 fancy ; and if the water be kept in purity, the lovely crea- 

 ture will survive an indefinite period. It needs to be fed 

 at frequent intervals, or it will droop and die ; for it is one 

 of the most voracious of its class. Nothing in the way of 

 flesh or fish comes amiss to it : a day or two ago I had an 

 instructive example of its gluttony. I had just dropped 

 two large ones of the variety Smaragdina into my col- 

 lecting-jar, when I succeeded in capturing a young Conger 

 Eel, about six inches in length and half an inch in thick- 

 ness. I wish that the sciolists who deny a poisoning 

 power to the organs of the Actinio'ids had seen the 'result 

 of the introduction of the lithe and vigorous fish to the 

 expectant Anthece. Before it could reach the bottom of the 

 jar, the green tentacles of one of the Opelets had entwined 

 themselves around its head, and, wrapping the wretch 

 around as if with a cloth, almost in an instant had dragged 

 it to the cavernous mouth, in which it was partially 

 engulphed. My little son, who was with me, begged for 

 the life of the fish ; and I drew it by force from the green 



