Fig. 4. 38. A, B. Chattonella subsalsa Biecheler; length, 30-50^; surface 

 view showing chromatophores, ventral groove, and basal portions of flagella; 

 optical section showing chromatophores, nucleus, and flagellar connections 

 (after B.). C. Merotrirhia capitatu Skuja, showing ventral groove, chromato- 

 phores, and "trichocysts"; x550 (after S.). D. Nuclear cap and flagellar con- 

 nections in Vacuolaria virescens; schematic (after Poisson and HoUande). 

 E. Vacuolaria viridis (Dangeard) Senn, longitudinal section of stained speci- 

 men showing nucleus, "gidlet," and chromatophores; diagrammatic (after 

 Fott). F. Vacuolaria virescens Cienkowski; length, 50-150^; stained specimen 

 showing chromatophores, contractile vacuole, nucleus and nuclear cap; sche- 

 matic (after Poisson and Hollande). G. Dividing nucleus of V. virescens; 

 diagrammatic (after Poisson and Hollande). H-J. Gonyostomum semen 

 Diesing, length 40-65;^. H. Diagrammatic optical section showing chromato- 

 phores, trichocysts, nucleus (in outline), and contractile vacuole lateral to 

 "reservoir" (after Chadefaud). I. Ventral view, showing groove and flagella. 

 J. Optical section showing outline of nucleus and reservoir; diagrammatic 

 (after Drouet and Cohen). K. Fission in palmella stage, Vacuolaria virescens; 

 schematic (after Poisson and Hollande). 



