Mr. E. W. H. Holdsworth on Digestive Power in the Actinia?. 279 



skin of the ventral portions of the mackerel and whiting was 

 uninjured; and the fine metallic lustre untouched : hut I should 

 think it is hardly necessary to remind Mr. Lewes that, in the 

 most highly organized animals, portions of food difficult of 

 digestion are frequently unchanged when passed off in the ex- 

 cretions; so that the circumstance referred to can have no bear- 

 ing on the question of ordinary digestive power. 



The experiments on the food contained in perforated quills 

 also appear to me to he by no means so conclusive of the absence 

 of chemical action as Mr. Lewes thinks ; they rather favour the 

 suggestion I have thrown out as to the nature of the mucus 

 produced in the stomach. From the tenacious character of this 

 substance, it would pass through the perforations in the quill 

 far less readily than would the surrounding water, and conse- 

 quently the appearance of meat freely subjected to its influence 

 might reasonably be expected to differ from that of the partially 

 protected contents of the quill. Such, indeed, appears to have 

 been the case in Mr. Lewes' s experiment. We are told at page 

 216, " On examination of the ejected quills, I found no appre- 

 ciable difference between the contained meat and similar pieces 

 of meat left in the water during the same period : in one of 

 them, which had the meat protruding somewhat from each end 

 of the quill, there was a maceration of the protruded ends w r hieh 

 looked like a digestive effect \" but this effect, the author goes on 

 to say, was due to " maceration obviously of a purely mechanical 

 nature/' because the muscular fibre was not disintegrated. Why 

 obviously mechanical ? After what I have observed of the partial 

 and sometimes entire solution and disintegration of the food, 

 may I not as reasonably ascribe "what looked like a digestive 

 effect" to the obvious commencement of chemical action ? 



I have now mentioned some of the facts which lead me to 

 believe in the possession of ordinary digestive power by the Ac- 

 tiniadse. The cases I have noticed as bearing on the subject 

 are but a few out of many similar ones that have occurred to 

 me and, unquestionably, to other persons who have given their 

 attention to the matter ; for I cannot believe that when a Sea- 

 anemone becomes an occupant of my aquarium, it is thenceforth 

 gifted with new faculties, and learns to digest its food in a 

 manner unknown to its brethren in other tanks or along the coast. 



There are some other points relating to the Actinice, which 

 are treated of in ' Seaside Studies/ and on which the author 

 holds opinions at variance with those of most naturalists ; but 

 it must be observed that in almost every case he only brings 

 forward negative evidence in support of his views ; and I need 

 hardly say that, in matters of science, such evidence is not 

 always trustworthy. 



