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1907. Pororr, MrtHopt.—“ Depression der Protozoenzelle und der Gesch- 
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1903. Surry, Grorrrey.—“‘ Actinospherium eichhorni: a Biometrical 
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metrica,’ vol. il. 
EXPLANATION OF PLATE 24, 
Illustrating Miss Doris L. Mackinnon’s paper on “A few 
Observations on the Encystation of Actinospherium 
eichhorni under different conditions of Temperature.” 
(For Fig. 1 see text, p. 412.) 
Fre. 2.—Occurrence of two nuclei in one primary cyst previous to primary 
karyokinesis. (B 9, cold.) 
Fre. 3.—To illustrate occasional retention of dead nuclei in the common 
cyst-envelope. (B49, cold.) 
Fig. 4.—Chromidia in primary cyst after primary karyokinesis. (B 8, 
cold.) 
Fic. 5.—Unsuccessful attempt to form primary cysts. (B11, cold.) 
Fic. 6.—Mother-cyst dying off, with 278 “dead” nuclei. (B11, cold.) 
Fic. 7.—One cyst containing six nuclei and 14 “dead” nuclei (?). (A 2, 
warm.) 
Fic. 8.—Group of primary cysts, in course of primary karyokinesis, showing 
ejected nuclei. (B 2, cold.) 
Fie. 9.—Group of conjugation-cysts and secondary cysts, in course of polar 
body formation, showing ejected nuclei. (A 2, room temperature.) 
All, except Fig. 8, are drawn from sections 10 p thick. 
Fig. 8 is from a preparation still in toto. 
All were fixed with picro-acetic acid and stained with borax carmine. 
6 and 7 were afterwards stained with Delafield’s hematoxylin. 
All figs. are enlarged 193 diameters. 
