230 MURIEL ROBERTSON. 
Fic. 4.—Radial Pseudospora. ec. v. Contractile vacuole. # Food particle 
contained in a vacuole. 
Fic. 5.—Transitory spindle shape adopted by a radial Pseudospora. 
Fic. 6.—Pseudospora attacking an unsegmented Parthenogonidium (p.). 
Fic. 7.—Early stage of mitosis. &. Karyosome. ch. Chromatin come 
together in irregular masses. 
Fie. 8.—sp. Spindle. c%. Chromosomes arranged in an equatorial plate. 
Fic. 9 a.—Chromosomes at separate ends of the spindle. c.f Central fibres. 
Fic. 9 .—Nuclei reforming. c.f. Central fibres being nipped across. 
Fie. 10.—Karyosome reforming. ch. Masses of chromatin. 
Fic. 11.—Pseudospora immediately after division. «. Nucleus. 
Fic. 12.—Pseudospora leaving the colony. 
Fie. 13 a.—k. Karyosome. 7. Thickened rays terminating at the nuclear 
membrane. The protoplasm has shrunk a little away from the nucleus. 
Fic. 13 6.—z. Karyosome. ch. 1, Chromatin masses on the outside of the 
sphere. ch. 2. Chromatin masses inside the sphere. spd. Sphere. m. 
Membrane. 
Fic. 14.—k. Karyosome. . Nuclear masses in the sphere: the karyosome 
is quite outside the sphere: the nuclear material has come together to form 
definite masses. 
Fic. 15.—The karyosome is outside the sphere, which has increased in size, 
definite nuclei are to be seen in the sphere. m. Last vestige of membrane 
with small masses of chromatin which are greatly reduced in size. 
Fic. 16.—Sphere shortly before segmentation. 
Fic. 17 a.—Segmentation of sphere, two segments formed, protoplaaaas 
body has not yet broken up. 
Fics. 17 6and 18.—Segmentation becoming irregular. 
Fic. 19.—Individual in which the gametes are already formed, although 
the protoplasmic body has not yet disintegrated. 
Fic. 20 a.—Gametes. 
Fic. 20 6.—Zygote with two flagella. 
Fic. 21.—Pseudospora with three spheres arising from one necleus. &. 
Karyosome. 
