ANTINIA. 199 



tubercle belonging to tbe Actinia mesembryanthemum, as may be seen on 

 the sides of its vessel, some time after the animal has fed. Likewise, 

 long white tendrils, of uncertain nature, occasionally protrude through the 

 sides of the Actinia maculata and of the clegans. Evidence of these facts 

 may be obtained on sudden removal of a turgid specimen of the first from 

 amidst its element, or by suddenly pouring off" the element from around it, 

 when streams will spout high from the distended tentacula ; and the ten- 

 drils will be exhibited by the others, on sustaining any irritation or pres- 

 sure. None of all these apertures, however, can be detected by simple 

 inspection. The skin is too intimately united, or it is too firmly closed 

 over them. The tips of the tentacula resemble perfect obtuse cones : the 

 tubercles are smooth and uniform, unless when opening in thin ragged 

 edges : nor can any mark denoting an orifice be discovered on the sides. 



One author is said to have proposed a generic distinction founded on 

 the diversity of the pores of the skin, — an equivocal guide. 



Certain organs belong to the interior of the Actinia, which are very 

 long, slender, and apparently tubular. They protrude along with inver- 

 sion of the stomach. But they are tubular only by the folding of the sides 

 together, for they can spread out like a very thin flattened membrane, an 

 inch wide. I have seen them do so, particularly in the Actinia crassi- 

 cornis. 



The active faculties of the Actinia being truly confined to simple 

 extension, expansion, contraction, and the slowest motion, utterly dis- 

 qualify it for the pursuit of prey. As the tide flows, it swells to its utmost 

 dimensions, and remains stationary, awaiting the accidental contact of 

 that congenial to its appetite, which it may seize, retain, and destroy. 

 Thence have the provisions of Nature rendered the stomach susceptible of 

 extraordinary dilatation, so as to be susceptible for reception of whatever 

 shall be casually presented. On the other hand, as little pabulum may be 

 afforded by large substances, the animal is guarded from perishing by that 

 famine which it must frequently suffer in patiently enduring lono- ab- 

 stinence. 



The whole body of some species is endowed with an external adhe- 

 sive faculty : the basis of all possesses it in the highest degree. The skin of 



