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BOTANIC LEAFLETS 
HAR UNIVERSITY 
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Cammripce, Massacnuserrs, JuLy 18, 1947 VoL. 12, No. 10 
A CONSPECTUS OF THE GENUS CUNURIA 
BY 
J.T. Batpwin, Jr.’ anp RicHarp Evans ScHULTES’ 
THE writers of the present article became interested 
in the euphorbiaceous genus Cunuria as the result of in- 
dependent field studies of Hevea, the genus of the Para 
Rubber Tree. These genera are related, and, indeed, it 
has been suggested (Baldwin in Journ. Heredity 38 
(1947) 54; in Am. Journ. Bot., in press, ‘‘Hevea rigid- 
ifolia’’) that they possibly have hybridized. A critical 
classification of the several concepts of Cunuria and an 
understanding of their geographic distribution may con- 
tribute greatly to an interpretation of the complex of 
genera to which Cunwria shows affinities. 
I 
Cunuria belongs to the tribe Jatropheae. The genus 
appears to be related to Micrandra, Hevea, Joannesia, 
and Nealchornia, and has especially close affinities with 
Micrandra and Hevea. Bentham (in Journ. Linn. Soc., 
Bot. 17 (1880) 185-268) observed that the first four of 
1Professor, William and Mary College; Collaborator, Rubber Plant 
Investigation, Bureau of Plant Industry, Soils and Agricultural En- 
gineering, U.S. Department of Agriculture. 
*Botanist, Rubber Plant Investigations, Bureau of Plant Industry, 
Soils and Agricultural Engineering, U.S. Department of Agriculture ; 
Research Fellow, Botanical Museum, Harvard University. 
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