PLATE LVII. 



PIGS. 



1-5. Amphitrema flavum (Archer) Penard. (p. 148) Figs. 

 1-3. Narrow, oral, and broad views. Fig. 4. 

 Broad view of an individual containing zoochlorellas 

 with a transverse constriction as if a process of 

 division were taking place; further stages have not 

 been observed. Fig. 5. Active individual contain- 

 ing zoochlorellae ; a broad short form which might 

 possibly be derived from a process of division as 

 suggested by Fig. 4. All x 500. 



6-8. A. wrightianum Archer, (p. 149) Figs. 6-7. Broad 

 and narrow views. x 500. Fig. 8. JJroad and 

 narrow views of a test from the peat deposit on 

 Clare Island, Mayo ; the covering of silicious parti- 

 cles, etc., having probably fallen off owing to decay, 

 x 250. 



"9, 10. A. stenostoma Niisslin. (p. 151) Broad and narrow 

 views of an active individual. x 500. 



