1912] YAMANOUCHI—CUTLERIA 



493 



WlSSELIN 



Kenntniss der Karyokinese) . Bot. Zeit. 56:195-226. pi. 10. 1898. 

 68. , Uber Kerntheilung bei Spirogyra (Dritter Beitrag zur Kenntniss 



der Karyokinese) . Flora 87:353-386. pi. 15. 1900. 

 fy)* , Untersuchungen iiber Spirogyra (Vierter Beitrag zur Kenntniss der 



Karyokinese). Bot. Zeit. 60:115-138. pi. 5. 1902. 

 70. Wolfe, J. J., Cytological studies on Nemalion. Ann. Botany 18:607-630. 



.pis. 40, 41. 1904. 

 Yamanouchi, S., 



figs. j. pis. IQ-28 



Bot. Gaz. 42:401-449. 



72. , Sporogenesis in Nephrodium. Bot. Gaz. 45:1-30. pis. 1-4. 1908. 



73- — , Mitosis in Fucus. Bot. Gaz. 47:173-197. pis. 8-11. 1909. 



74* ~ -, Cytology of Cutleria and Aglaozonia. Bot. Gaz. 48:380-386. 



1909. 



75* , Chromosomes in Osmunda. Bot. Gaz. 49:1-12. pi. 1. 1910. 



7"- , On the life history of Zanardinia collaris Crouan (a preliminary 



note). Bot. Magazine Tokyo 25:10-12. 191 1. 



EXPLANATION OF PLATES XXVI-XXXV 



All figures were drawn with the aid of a camera lucida under the Zeiss 

 apochromatic objective 1 . 5 mm. N.A. 130, in combination with compensating 

 ocular 12; except figs. 200-202, which were drawn with compensating ocular 

 18; figs. 8, 9, 14, drawn with compensating ocular 8; and figs. 1-7, 12, 13, 16, 17, 

 53, 144-15°, drawn with ocular 4; and figs. 10, n, 15, which were drawn under 

 Zeiss apochromatic objective 16 mm. combined with compensating ocular 12. 

 The figures are reduced to one-half the original size. Figs. 1-15 are in the text. 



PLATE XXVI 



The formation of the male gametangium of Cutleria midtifida 



Fig. 16. — Portion of the thallus of a male plant, showing a single layer of 

 superficial cells and the larger cells below. 



Fig. 17. — Portion of the thallus of a male plant, where 4 superficial cells 

 have grown into papillae, the male gametangium initials. 



Fig. 18. — Male gametangium initial: nucleus in resting condition. 



Fig. 19. — Prophase of nucleus: 24 chromosomes and a nucleolus present. 



Fig. 20. — Metaphase: the nuclear cavity in this stage strikingly diminished. 



Fig. 21. — A filament with two male gametangia: nucleus in the young 

 gametangium initial at metaphase. 



Fig. 22.— Anaphase that follows the metaphase of fig. 20. 



Fig. 23.— Nucleus already divided and each daughter nucleus now in 

 prophase; 24 chromosomes present in each. 



Fig. 24.— Nucleus in the lower cell in advanced prophase, while the nucleus 

 in the upper cell is still in early prophase. 



