ACKNOWLEDGMENTS 
The initial investigations upon which this paper is 
based were supported by the Longwood Foundation, 
Inc. The author would like to thank Dr. Russell J. 
Seibert, Director of Longwood Gardens; Dr. D. G. 
Huttleston, and other members of the Longwood Gar- 
dens staff for their assistance and encouragement. 
This work was also supported, in part, by a National 
Science Foundation Grant (GB-35047), The Society of 
the Sigma Ni, and the Biology Department of Harvard 
University. 
The following persons have offered suggestions for 
improving the foregoing presentation: R. E. Schultes, 
Rolla M. Tryon, L. I. Nevling, Jr., C. E. Wood, Jr., 
A. S. Barclay, and T. Plowman. Their assistance is 
sincerely appreciated. 
