32 BOTANICAL GAZETTE funy 
18. TimpertakE, H. G., Develoment and structure of the swarmspores of 
Hydrodictyon. Trans. Wis. Acad. Sci. 13:486-521. pls. 29, 30. 1902. 
19. YAMANOUCHT, S., The life history of Polysiphonia. Bor. Gaz. 42:401-440. 
fig. 3. pls. 19-28. 1906. 
20. ———, Mitosis in Fucus. Bor. Gaz. 47°173-197. pls. 8-11. 1909. 
, On the life history of Zanardinia collaris Crouan (a preliminary 
note). Bot. Mag., Tokyo 25: 10-12. IQII. 
, The life history of Cuileria. Bor. Gaz. 54:441-502. fig. 16. 
pls. 26-35. 1912. 


EXPLANATION OF PLATES I-IV 
All figures were drawn with the aid of a camera lucida and Zeiss apochro- 
matic objective 1.5 mm. N.A. 130, in combination with compensating ocular 
12; except figs. 2-4, 17, 19-21, and 24, which were drawn with compensating 
ocular 4; figs. 16 and 23, which were drawn with compensating ocular 8; 
and fig. 18, which was drawn under Zeiss apochromatic objective 16 mm. com- 
bined with compensating ocular 12. The figures are reduced to one-half 
the original size. F igs. 1-24 are in the text. 
PLATE I 
‘Union of gametes and germination of fertilized female gamete 
Fic. 25.—Six male gametes which have ju 
ment: cilia withdrawn, nuclear membrane 
showing 22 chromosomes. 
Fic. 26, 
stage. 
St stopped the swimming move- 
scarcely visible, and reticulum 
—Female gamete which has become quiescent: nucleus in resting 
; ho cell membrane has 
formed around the gametes. 
I 
—Body of male gamete still visible as a slight protuberance on 
; dividual chromosomes in male gamete nucleus. 
Fic. 29.—Cytoplasm of male gamete entirely fused with that of female, 
ast whole body of united gametes about spherical; male nucleus still shows 22 
chromosomes, 
1G. 35.—Early prophase of fusion nucleus: ‘ 
olus present; all the chromo: €us: 44 chromosomes and a nucle 
somes apparently alike both in form and size. 

