Figure 1.

Epixenosomes and their host. (a) Dorsal view of E. itoi at scanning electron microscope. Arrows indicate epixenosomes in the cortical band. (Bar = 100 μm.) (b) Sectioned stage I epixenosomes. Arrow indicates the dividing one. (c) Stage II epixenosomes sectioned at different levels. DZ, Apical (dome-shaped) chromatin-like zone. EA, Extrusive apparatus. BT, Microtubule-like elements forming a “basket” around EA. (d) Section through the head of an ejected epixenosome. (Bars = 1 μm.) (e) The tube at the end of ejection. ER, Epixenosome remnant. H, Head. (Bar = 10 μm.)