322 Dr. A. Gruber on Protozoa. 



causing one of the numerous small Actinophryes present to 

 approach a full-grown one in such a manner that it 

 remained attached to its pseudopodia. Immediately it 

 quickly approached the larger specimen or was drawn in by 

 the latter ; the pseudopodia partially fused together, and a 

 bridge of protoplasm began to unite the two individuals 

 (fig. 9). In about five minutes they were already for the most 

 part fused together. At this moment the Ileliozoa were killed 

 as above described, stained, and mounted. During this it 

 appeared that the smaller individual had possessed no nucleus 

 at all. "While in the larger Actinophrys the nucleus stands 

 out from the surrounding protoplasm in the centre as distinctly 

 as possible, no trace of any thing of the kind is to be recog- 

 nized in the smaller one*. This explained why, in the pre- 

 viously cited process of fusion, only one nucleus was to be 

 detected in the coalesced Heliozoa. 



I have since frequently repeated this experiment, and 

 always with the same result. I also succeeded in causing 



I r 



large ActinopJiryes furnished with nuclei to unite by bringin 

 them artificially into contact. In this case, however, the 

 union only took place slowly, while in the former it was 

 rapidly effected ; and although in the latter cases the outer 

 contours did not indicate that two individuals were united, 

 this could be clearly discerned from the two nuclei. Fre- 

 quently the two approximated Heliozoa repulsed each other 

 again — a proof that the union takes place consciously, if we 

 may use such an expression. In favour of this we have also 

 the circumstance that even the small individuals of Actino- 

 phrys are not always incepted. I once succeeded in conveying 

 to a large specimen three small ones one after the other, all of 

 which were absorbed by it, notwithstanding that several green 

 food-particles were also received. I have represented the in- 

 dividual in question in fig. 10, and indeed at the moment 

 when two of the small parts were almost amalgamated, while 

 the third had already passed entirely into the protoplasm of 

 the large Actinophrys, in which the above-mentioned green 

 bodies were also imbedded. This individual now persistently 

 refused to take up a fourth small Heliozoan which was brought 

 close to it, always pushing the latter away from it, evidently 

 because it was not disposed to undergo any further increase of 

 substance. 



It seems to me therefore that the observed processes have 

 really no other signification in the ease of Actinophrys than 



I may remark here that the difference of size between the coloured 

 and living Actinopliryes is always considerable, as the former are strongly 

 contracted by the absolute alcohol. 



