Mr. E. W. H. Holdsworth on Digestive Power in the Actinia). 275 



his sutura vittaque submarginali, nigria ; antennia nigris, articulis 

 basalibus obscure piceis. — Long. 3f lin. 

 Hob. Brazil. 



(Edionychis virginella. 



(E. oblongo-ovata, nitido-fusco-fulva, tibiis tarsisque posticis, pedibus 

 quatuor anticis antennisque rufo-fuscis, tborace elytrisque albidis, 

 bis subrectis, ltevibus, obsolete punctulatis. — Long. 3^ lin. 



Hub. San Paulo, Brazil. 



XXIX. — On Digestive Power in the Actiniae. 

 By E. W. H. Holdsworth, F.L.S. &c. 



To the Editors of the Annals of Natural History. 



Gentlemen, 



Mr. G. H. Lewes having recently published, in ' Seaside 

 Studies/ his views of the digestive powers of the Actinia, criti- 

 cism becomes allowable; I therefore propose to offer a few 

 remarks on the subject, and to relate my observations made 

 during a long course of study of these animals. If I cannot 

 always agree with Mfi Lewes, still I have no wish to depreciate 

 the value of his researches ; and my sole object in stating what 

 I have observed is to aid in the settlement of the point in 

 dispute. 



In •' Seaside Studies/ page 207, will be found the brief query 

 — " Do the Actiniae digest at all V Mr. Lewes then proceeds 

 to give his definition of digestion, and concludes by saying, — 

 u Thus we see that solubility and transformation are the two 

 digestive effects, to produce which two agencies are needful — 

 the mechanical and chemical." The first is the one adopted by 

 the author as the sole means of preparing the food for assimila- 

 tion in the Actinice. 



In order to test the accuracy of this opinion, it will be desir- 

 able to notice what takes place when these polypes are fed. 

 Any one who has healthy specimens in an aquarium can easily 

 try the experiment, and will observe something like the follow- 

 ing process : — 



A piece of meat, of suitable size, after being conveyed to the 

 mouth of the polype, is taken into the membranous tube, gene- 

 rally considered as the stomach, where it remains for a few mi- 

 nutes only, and sometimes barely stops there; it then passes 

 into the general cavity of the body, and finally rests at its lowest 

 part. The animal now fills itself with water until every part is 

 distended to the utmost, and in this state it continues for several 

 hours, not unfrequentlv for two days, the average time perhaps 



18* 



