CLASS GREGAKINIDA. 277 



film over the enclosed mass. The food is gradually absorbed by 

 the coating of this extemporized stomach. The processes thus 

 shot forth and answering as hands or feet are termed psendopo- 

 dia (false feet). In those species protected by a shell there is the 

 same power of throwing out pseud opodia at the orifice for 

 locomotion or prehension, and in the latter case, of transpos- 

 ing the prehensile instrument into a mouth or alimentary 

 canal. Eeproduction is by fission, budding and cysting, a 

 detached pseud opodium being developed sometimes into a 

 separate animal. When, by budding, the new Ehizopod re- 

 mains attached to the shell of the parent, in some species, 

 particularly the Foraminifera (hole-bearing),* it gives rise to 

 the beautiful aggregated forms known as Nummulites, Globi- 

 germas, etc. 



CLASS GREGARINIDA. 



General Characteristics. The Gregarinidans (flocks) 

 are parasitic forms found particularly in Cockroaches and 

 Earth-worms. They give out no pseudopodia, 

 and assimilate food only by the absorption on 

 the general surface, as is common in internal 

 parasites. Their anatomical structure usually 

 presents a single cell, having in it, among fatty 

 granules, a central vesicle, itself enclosing a 

 solid particle. Elongation and contraction of magnified. 

 the body are the ordinary signs of life. 



Still lower forms, however, are revealed by the microscope, 

 as the Monera, comprising the genera Bathybius, Prot- 

 amoeba, etc., by some Naturalists disbelieved in as 

 really organic beings, and by others doubtfully 

 referred to the Vegetable rather than to the Animal 

 Kingdom. Of these Batliybius,\ a mass of albumin- 

 ous jelly neither distinctively animal nor plant, is 

 considered the simplest structure known to man. 



* See " Fourteen Weeks in Geology," pp. 188 and 198. 



t Recently Huxley retracts his opinion concerningtiathybius as having vitality. 



