LATTICE WORKERS, OR POLYCYSTINA. 79 



indigestible portion, this, after the digestion of the 

 soft parts, is gradually pushed towards the surface, 

 and at last escapes by an anal opening, which ex- 

 temporises itself for the occasion. 1 The reproductive 

 process in Actinophrys is still in need of further 

 elucidation. Binary subdivision is one method, in 

 which the body is constricted all round, which con- 

 striction gradually deepens, until the connecting 

 band becomes thinner and thinner, and complete 

 separation takes place. This process occupies about 

 half an hour. It has also been affirmed that the 

 junction of two individuals has been seen to take 

 place, which has been assumed to correspond to 

 conjugation in certain Algae, but there is not 

 sufficient evidence to associate this union with 

 an act of reproduction. Other appearances have 

 also been detailed, from which it has been inferred 

 that true sexual products are formed in the in- 

 terior of the bodies, and that spermatozoids are 

 liberated and ovules fertilised. " Nicolet has stated 

 that in Actinophrys the generative organs consist 

 of a central spherical membrane, enclosing little 

 globules, which are the rudiments of 'eggs,' sur- 

 rounded by a ' gelatinous granular layer,' the granules 

 of which appear to be the reproductive organs," but 

 this view is doubted, and has not been substantiated. 



1 Dr. Carpenter : " Introduction to the Foraminifera," p. 19. 



