THE POLLINATION OF MARCGRAVIA: A CLASSICAL 
CASE OF ORNITHOPHILY? 
Irving W. Bailey 
(Received for publication December 12, 1921) 
Introduction 
Since the publication of Darwin's investigations upon the polHnation 
of orchids, many biologists have tended to assume that flowers which 
are visited by insects and birds are pollinated by these animals, and that 
aberrant types of floral organization are adaptations to insure cross-pol- 
lination. Thus, the bizarre inflorescences of Marcgravia, with their curious 
pitcher-like nectaries, are assumed to facilitate cross-pollination by birds. 
In fact, this extraordinary genus is cited as one of the most striking illus- 
trations of ornithophily. 
E 
Fig. I. Nectariferous appendages of Marcgraviaceae. A. Marcgravia coriacea Vahl. 
B. M. picta Willd. C. Norantea giiianensis Aubl. D. Sourouhea pilophora Wittm. E. S. 
guianensis huh\. F. Ruyschia sphaerodenia Delp. After Wittmack. 
While collecting along the banks of the Mazaruni and Cuyuni Rivers 
near the Tropical Station of the New York Zoological Society,^ the writer 
encountered two species of Marcgravia. As much time as could con- 
veniently be spared from other work was devoted to a study of the structure 
^ At Kartabo, British Guiana. 
