216 M. E. Claparede <>w Actinophrys Sol. 



by Actinophrys in tins way, continued to move for a little time> 

 endeavouring to break through the substance that enveloped 

 them; their movements, however, soon ceased; they became 

 converted into a globular mass, which circulated very slowly 

 through the parenchyma with the so-called vacuoles. The par- 

 ticle of food always lies in a cavity filled with fluid {vacuole of 

 Dujardin), but it could not be determined with certainty whether 

 this fluid was a product of digestion, a secretion assisting in that 

 function, or merely water sucked in with the food. As, how- 

 ever, the fluid always exhibited the same pale reddish colour as 

 the contents of the contractile vesicle, indicating different re- 

 fractive powers from those of water, the last supposition could 

 not be supported. However this may be, the process of diges* 

 tion always requires a considerable time. I once followed the 

 changes of a Chlamidomonas which had been swallowed by an 

 Actinophrijs ] small as the object was, three hours scarcely 

 sufficed for its conversion into an unrecognizable gelatinous 

 mass. 



This mode of feeding is exceedingly remarkable, and it must 

 be admitted, not very easy of comprehension. At first I thought 

 that the substance which so suddenly enveloped the object to be 

 swallowed, was produced by the mere bending, expansion and 

 fusion of the tentacles. I could not, however, retain this opi- 

 nion; an extension of a mucous substance, apparently the paren- 

 chyma, really takes place from the side of the ActinophrySy and 

 this is afterwards drawn in with the prey. This expansion 

 sometimes takes place very slowly. A thick, regularly lobed 

 mass is seen to embrace the object (fig. 4 o), and I have once 

 observed this extension without the presence of any prey (fig. 4 h). 

 I can only compare this process with what takes place in Amoeba. 

 Dujardin indeed asserts that the Amoebae are nourished by the 

 mere imbibition of fluid, and that the particles of food found in 

 them come there by accident. This statement, however, is not 

 in accordance with facts. The Amoebae really feed in a very 

 remarkable manner; they glide slowly along, and draw them- 

 selves like a veil over the objects to be swallowed ; one would 

 suppose that the objects still lay beneath them, but they are 

 already enclosed within the body. We may observe in passing 

 that it appears almost absurd to attempt the distinction of 

 species amongst the Amoeba until we know something more of 

 their intimate organization. Thus Ehrenberg^s A. radiosa is 

 characterized by the regularity of its processes and its generally 

 stellate form ; but when the creature creeps and feeds, it slowly 

 expands, and its characteristic form disappears ; it flows along 

 like a cloudy veil or a drop of oil, and A. radiosa j Ehr. has 

 become converted into A. diffluens, Ehr. Arcella vulgaris un- 



