FARR: QUADRIPARTITION IN SISYRINCHIUM 61 
‘ Das botanische Praktikum. Jena. 1884. 
23. Tackholm G., & Soderberg, E. Ueber die Pollenent- 
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die phylogenetische Bedeutung des Pollentypus. Ark. 
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24. —— Neue Beispiele der simultanen und_ sukzessiven 
Wandbildung in den Pollen-mutterzellen. Svensk. Bot. 
Tidskr. 12: 189-201. f. 1-9. 1918 
25. Tieghem, Ph. Van. L’oeuf du jileeniteas considére ns werk 
de la classification. Ann. Sci. Nat. Bot. VI. 
464. I9O1 
26. Valleau, W. D. Sterility in the strawberry. Jour. Agr. 
Research 12: 613-6.70 pl. B-E+ 35, 36. 1918. 
27. Yamaha, Gihei. Einige Beobachtungen iiber die Zellteilung 
in der Archesporen und Sporenmutterzellen von Psilotum 
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1920. 
Description of plate 2 
Fic. 1. Photomicrograph of a longitudinal section of an anther of 
Sisyrinchium Bushii. The cells in the outer end are in the metaphase of 
the oe and those at the inner end are in metaphase of the homoeo- 
typic a 
Fic — of an anther at a slightly later stage of develop- 
ment. The cells at the inner end are in metaphase of the homoeotypic 
mitosis and those at the outer end are in the tetranucleate stage just prior 
to furrow formation. 
3. A drawing of a cell in cytokinesis. The furrows are partly 
formed and the central triangular area is appearing. 
JNn 
QQ 
