Sahni — On the Branching of the Zygopteridean Leaf 379 
Seward, who has been a constant source of help and encouragement. This 
work was carried out during the tenure of a Research Studentship at 
Emmanuel College, Cambridge, and of a grant from the Dixon Fund of the 
University of London. 
The Botany School, Cambridge, 
November 6, 1917. 
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* 
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