CORALS AND CORAL MAKERS. 21 



appeared, and in this case " they do not at first show any signs 

 of activity, but on the contrary remain for a long time in a 

 quiet state, having the appearance of artificially separated 

 pieces, seeming to be undergoing, as in the latter, a recupera- 

 tive process after the shock of a separation." After a while 

 they commence to develop and grow into perfect individuals. 

 Prof. Verrill mentions the case of an Actinia from Puget's 

 Sound (the Epiactis prolifera, V.) which had three rows of 

 young individuals attached to it around the middle of its 

 body ; but whether the young Actiniae were produced by bud- 

 ding from this part of the body, or whether they had colonized 

 there after being produced in the ordinary way, he was unable 

 to determine. In all cases the young ultimately separate from 

 the parent. 



These polyps have also the faculty of reproducing lost parts ; 

 and to such an extent that a mere fragment, if it be from 

 the lower part, and include a portion of the base, will repro- 

 duce all the rest of the Actinia, even to the disk, tentacles, 

 and stomach. Thus the mere forcible tearing of an Actinia 

 from the rock to which it is attached may result in starting a 

 crop of new Actiniae. 



Although Actiniae have no internal coral secretions, they 

 sometimes make a thickened epidermic plate at the base, and 

 also in a few cases around a part of the body. This is how- 

 ever not a result simply of an epidermic secretion, but arises 

 from an exudation of mucus from the surface, and the entang- 

 ling thereby of minute particles of foreign or dead matters. 

 A case of the kind, in an Edwardsia where the body is thus 

 encased, is mentioned and explained on page 9. 



The above are the more prominent characters of the 

 Actinia tribe of polyps. The special features distinguishing 

 them from the coral-making polyps are the following : (i) They 

 are simple animals, or, if they bud, the buds early separate 

 from the parent; (2) They have a muscular base; (3) They 

 are generally capable, more or less perfectly, of locomotion on 

 the base by means of its muscles ; (4) They sometimes possess 

 rudimentary eyes; (5) They have no internal coral secretions. 



