ACTINIAE. 47 



barbed spines of inconceivable minuteness, but formidably effective 

 for their purpose. On the slightest irritation, the spiral thread 

 bursts forth and entwines the victim in its spiny folds, which seem 

 to be armed with some potent venom, as a small animal once 

 seized by them dies, even should it escape from their tenacious 

 grasp. 



The Actinia;, like the Hydrae, seem to defy the effects of mutilation : they may be 

 cut in two perpendicularly or across, and each cutting will soon furnish forth the want- 

 ing parts, and present itself in all respects well and hearty. MR. GOSSE. 



In some species, when a large individual has been a good while 

 adherent to one spot, and at length chooses to change its quarters, 

 it does so by causing its base to move slowly along the surface on 

 which it rests. But it frequently happens that small irregular 

 fragments of the edge of the base are left behind, as if their ad- 

 hesion had been so strong that the animal found it easier to tear 

 its own tissues apart than to overcome it. The fragments so left 

 soon contract, become smooth, and spherical or oval in outline , 

 and in the course of a week or a fortnight, may be seen each fur- 

 nished with a margin of tentacles, and a disk transformed, in 

 fact, into perfect though small Actiniae. Occasionally a separated 

 piece, more irregularly jagged than usual, will, in contracting, 

 form two smaller fragments, each of which becomes a separate 

 animal. Dr. T. Strethill Wright cut off a minute piece of the base 

 of a sea-anemone; the part immediately receded from the parent, 

 and in three weeks became a perfect Actinia ; he then cut pieces 

 from these with the same result, and ultimately get fourteen from 

 the original one. 



The ordinary mode of reproduction in these Zoophytes is by 

 minute germs or ova, which are to be found suspended in dense 

 clusters in the interior of the animal : these escape into the 

 creature's stomach, and are discharged into the sea through the 

 mouth. Some of the Actiniae are exceedingly prolific, producing 

 from a hundred and fifty to three hundred young in a single day. 

 The characteristic form and markings of the parent are distinctly 

 recognizable in the newly-born progeny, the principal distinction, 

 besides the difference of size, being the fewness of the tentacles, 

 which at first are only about twelve in number. 



The Mushroom Corals (Fitngia)* are so called on account of a striking 

 resemblance between the arrangement of the stony laminse upon the upper 

 surface of their framework and the gills of a mushroom (Fig. 42). This, 



* Fungus, a mushroom. 



