Beccari and Rock — Pritchardia. 9 



met with in the pollen grains of Pr. affiiiis, is probably common to all species of 

 Pritchardia, considering the very small differences existing among their flowers. 

 According to Professor Rock, the flowers of Pritchardias are much frequented by 

 bees, wasps, and other insects; hence it is not improbable that birds also visit them 

 to capture those insects; yet if the flowers of these palms do secrete a nectareous 

 juice, it is presumable that the Drcpanidi, the family of birds so peculiar to the 

 Hav.'aiian Islands and which possesses a form of beak especially adapted for 

 extracting nectar from the flowers of various plants, visit the Pritchardias as well, 

 thus contributing indirectly to their fertilization. 



It is also possible that some Pritchardias may produce two qualities of flow- 

 ers from the same spadix; flowers which in appearance morphologically conform, 

 but which are in fact functionallv dift'erent. And with respect to this. Professor 

 Rock has pointed out to me that in Pr. Bcccariana, in Pr. Martii, and perhaps in 

 some other species, only the uppermost branch of every spadix produces the fruits, 

 while all the flowers on the lower branches fall off. Hence in these species we have 

 spadices of a clearly heterogamous nature. But in the specimens of Pr. Bcccariana 

 examined I have not discovered any organic dift'erence between the flowers from 

 the lower branches and those from the upper part of the same spadix. 



STRUCTURAL PECULIARITIES. 



The diagnostic characteristics of the species of Pritchardia are found chiefly 

 in the fruit, and in the indumentum which covers the leaves and the spadices. 

 Characters which might serve to distinguish one species from another are hard to 

 find in the flowers, as these conform to one type, with slight dift'erences in size and 

 in the venation of the calyx and of the corolla. Only Pr. JVrigJitii differs from the 

 Polynesian species, its flowers being of a more fleshy nature than those of others of 

 the entire group. 



The leaves of Pritchardia are without stom'ata in their upper surface but 

 almost always show some special covering or clothing on the lower. Only in a very 

 few cases are they equally green and bare on both faces. The indumenta which 

 cover the leaves and other parts of the plant are of two different kinds. One 

 consists of a thin waxy coating, which takes the appearance of a fine white powder, 

 easilv removed, and which imparts to the petioles, to the backs of the leaves, and to 

 parts of the spadices a powdery and glaucous shade more or less pronounced, as in 

 Pr. Thurstouii. Pr. HiUchrandi. Pr. Maideniana, and Pr. insignis. The other far 

 more common indumentum is due tn the presence of a special kind of hairiness, or 

 of dots like orbicular or oblong or variously shaped scales, which I have distin- 

 guished with the name "lepidia"' and which are present on the leaves of many other 

 palms. When the Icjiidia are very close together they form a complete covering, 

 touching each other with their marginal cells, which in some cases take the shape 



e Webbia, vol. IV, p. 366, 1913. 



