MONERA. 



Organisms without organs. The entire body consists of nothing more than a bit 

 of plasma or primitive jelly, an albumenoid compound not differentiated into proto- 

 plasm and nucleus. Every Moner is therefore a cytode but not a cell. Their form is 

 indefinite, with lobes or pseudopodia projecting from any part, by means of which they 

 move. They multiply by division, budding, or by the formation of spores, as will be 

 described further on. They live mostly in water. The manner in which the Monera 

 envelop and flow around their food shows the absence of a definite limiting membrane 

 or cell-wall, and also the extreme simpUcity and homogeneous character of their body 

 substance ; since any portion of it surrounding a particle of food causes digestion and 

 assimilation to take place. This method of securing food will be more fully described 

 when treating of the Ammba. The reproductive processes are rather more complex 

 than would be anticipated 

 among such low forms of life. 

 The simplest method of propa- 

 gation is by division of the or- 

 ganism into two parts by a 

 construction across the middle, 

 forming two animals precisely 

 like the parent form. 



The Protomyxa auranti- 

 aca represented in Fig. 1, is a 

 typical Moner. It is shown at 

 (/) in its active, creeping con- 

 dition, the pseudopodia stream- 

 ing outward in all directions 

 with clear spaces or vacuoles 

 and food particles in the in- 

 terior. The food is entangled 

 in the reticulate pseudopodia 

 and gradually drawn into the 

 body, where a temporary stom- 

 ach is formed by the surround- 

 ing protoplasm. After the di- 

 gestible portions are absorbed 

 the rest is cast off from any 

 part of the surface. This 

 Moner multiplies by the for- 

 mation of swimming spores in 

 this manner: The pseudopodia 

 are all retracted and the Moner 

 becomes spherical (a). It then 

 becomes encysted by the for- 

 mation of a thick outer mem- 

 brane, meanwhile changing to an orange-red color. The cyst ripens by the sub- 

 division of the contents (6), and finally the enclosing membrane ruptures (c), and 

 the contents escape as bright red, active swarm-spores, which swim about by the aid 

 of the delicate, lashing flagella or threadhke extensions of the protoplasmic body. 

 These changes are iUustrated in the figure a, b, c, and d, being the successive stages 



¥ia. 1.— Protomyxa auriantiaca: a. encysted; b. division of proto- 

 plasm : c. cyst bursting, giving rise to the spores, d. e., from 

 which, by coalescence, the feeding Plasmodium,/., is formed. 

 Greatly enlarged. 



