Dr. A. Gruber on Protozoa. 323 



an augmentation of substance, and that in this way the as- 

 sumption that we have to do here with an act connected with 

 reproduction, such as a conjugation, is completely excluded. 



Perhaps, however, the fact that the above-mentioned small 

 individuals (as I have called them) possess no nuclei is directly 

 opposed to this view. This latter fact is remarkable enough ; 

 and I must enter upon it in further detail. The first question 

 is, How are the organisms described by me as small indivi- 

 duals to be conceived ? as perfect organisms or not ? 



To this it may be answered that they are nothing more 

 than products of the disintegration of larger Actinophryes, 

 and not the offspring of a Heliozoan by regular division. 

 This may perhaps be quite correct ; and a breaking-up into 

 irregular fragments does occur here, and, as I intend here- 

 after to show, also among the higher Protozoa, namely the 

 Infusoria. This, however, furnishes no reason why these 

 disintegration-fragments should not in the present case be 

 regarded as really individuals. 



Thus, if we examine one of these so-called smvW. Actinophryes 

 more closely, we find that in truth it does not differ essentially 

 from the perfect Actinophryes. At least there are specimens 

 which are quite regularly formed j and, at all events, all of 

 them are perfectly independent. Many certainly consist only 

 of a few vacuoles surrounded by scanty protoplasm, from 

 which one or two pseudopodia arise. But for the most part 

 they were of an approximately round form. The vacuoles 

 and protoplasm were distributed as in the full-grown animal ; 

 and numerous pseudopodia, often regularly arranged, radiated 

 from the margin. 



Further, the functions of these creatures are the same as 

 those of the nucleated Actinophryes. They move spon- 

 taneously from place to place ; they show rapid changes in 

 the pseudopodia ; in their interior we see nutritive bodies ; and 

 even the large vacuoles in which large food-particles are 

 digested are frequently to be seen. Finally, very often the 

 contractile vesicle is not wanting, and it pulsates rhythmically 

 in the same way as in the normal animals. Must we not 

 therefore designate these non-nucleated forms as independent 

 individuals ? It may be objected that even in the mode in 

 which the fusion takes place the imperfect independence of 

 the small parts is demonstrated, as they are actually swallowed 

 just like other prey. But the latter statement is not quite 

 correct ; for, until it has entirely passed into the other, the 

 small animal retains the faculty of extruding pseudopodia, 

 and, further, two non-nucleated Actinophryes may approach 

 each other and unite. 



