740 MICROSCOPIC FORMS OF ANIMAL LIFE PROTOZOA 



extemporises itself for the occasion ; but if small it sometimes glides 

 along a pseudopodium from its base to its point, and escapes from 

 its extremity. 



The ordinary mode of reproduction in Actinophrys seems to be 

 by binary subdivision, its spherical body showing an annular con- 

 striction, which gradually deepens so as to separate its two halves by 

 a sort of hour-glass constriction, and the .connecting band becoming 

 more and more slender, until the two halves are completely separated. 

 The segments thus divided are not always equal, and sometimes their 

 difference in size is very considerable. A junction of two individuals, 

 on the other hand, has been seen to take place in Actinophrys, and 

 has been supposed to correspond to the ' conjugation ' of protophy tes ; 

 it is very doubtful, however, whether this junction really involves a 

 complete fusion of the substance of the bodies which take part in it, 



FIG. 575. Marginal portion of Actinospli(erinm Eichomii 

 as seen in optical section under a higher magnifying 

 power : m, endosarc ; r, ectosarc ; a, a, a, pseudopodia ; 

 M, H, nuclei with nucleoli ; /', ingested food-mass. 



and there is not sufficient evidence that it has any true generative 

 character. Under these circumstances we must hope that Dr. F. 

 Schaudimi's preliminary notes of his observations 1 may soon be 

 followed by a more detailed account. This author claims to have 

 demonstrated the fusion of the nuclei of A. sol, and the resemblance 

 of the course of events to the maturation of the ova of higher 

 animals is very striking. Certain it is that such a junction or 

 ' zygosis ' may take place, not between two only, but even several 

 individuals at once, their number being recognised by that of their 

 contractile vesicles ; and that, after remaining thus united for several 

 i SB. Akad., Berlin, 1896, p. 49. 



