348 



PLATE III 



Fig. 1. Portion of fine pseudopodium, during life, of Polystomella. 



Fig. 2. The same of Cornuspira. 



Fig. 3. The same of Discorbina. 



Fig. 4. Thicker pseudopodial stem of a living Rotalina, with a very distinct 

 fibrous alveolar structure. 



Fig. 5. Small Aciiwta (see the text, p. 87) from fresh water. Living. The 

 structure of the protoplasm only partly filled in. g, the wall of the 

 envelope ; alv, alveolar layer ; mn, macronucleus ; cv, contractile vacuole 

 with the very distinct efferent canal ; x, dark bodies in the protoplasmic 

 framework. 



