114 BRITISH FRESHWATER RHIZOPODA. 



In describing the life-history and affinities of this 

 organism the author says :* ''Archerina is clearly one of 

 the non-nucleate Grymnomyxa (Homogenea or Monera), 

 and is, in so far as regards the various forms which 

 its protoplasm may assume, not far removed from 

 Cienkowski's Vampyrella. It is, however, definitely 

 characterized and distinguished by its nucleus-like 

 chlorophyl-corpuscle. No other Protozoon is known 

 the form of which is thus dominated by a chlorophyl- 

 corpuscle, nor is there any form with a chlorophyl- 

 bearing nucleus which might be compared with it. In 

 regard to nutrition it clearly gives evidence of both 

 plant-like assimilation of carbon through the agency 

 of its chlorophyl-corpuscles, and of the usual ingestive 

 voracity of the naked Protozoa." 



Elsewhere Prof. Lankester remarks : t " Archerina 

 exhibits an amoeba phase in which the protoplasm is 

 thrown into long stiff filaments surrounding a spherical 

 central mass, about one two-thousandth of an inch in 

 diameter (actinophryd form). A large vacuole (non- 

 contractile) is present, or two or three small ones. 

 No nucleus 'can be detected by a careful use of 

 reagents in this or other phases. The protoplasm 

 has been seen to ingest solid food-particles (bacteria) 

 and to assume a lobose form. The most striking 

 feature of Archerina is the possession of chlorophyl 

 corpuscles. In the actinophryd form two oval green- 

 coloured bodies are seen. As the protoplasm increases 

 by nutrition, the chlorophyl corpuscles multiply by 

 quaternary division and form groups of four or of 

 four sets of four symmetrically arranged. The division 

 of the chlorophyl corpuscles is not necessarily followed 

 by that of the protoplasm, and accordingly specimens 

 are found with many chlorophyl corpuscles embedded 

 in the large growth of protoplasm ; the growth may 

 increase to a considerable size, numbering some hun- 

 dreds of chlorophyl corpuscles, and a proportionate 

 development of protoplasm. Such a growth is not a 



* ' Q. J. Micr. Sci./ I.e. f ' Encycl. Brit./ I. c. 



