42 
COPELAND. 
plete physiological unit, the leaf and roots working together — 
so close together that the stem is hardly in evidence. The main 
rhizome produces these successive units and serves as their 
point of attachment, and also as a place of storage, at least 
of water. Except presumably in every young plants, which 
have not been seen, the rhizome bears no roots except numerous 
short ones confined to the side against the tree on which the 
fern grows. Their main function is certainly clinging; but they 
doubtless absorb some water, and very little food. In each sinus 
between the segments of the leaf is an evident gland, but I have 
seen no ants around these. For its mineral food the plant 
probably depends practically altogether on the detritus collected 
by the leaves. 
In the perfection of the humus-gathering apparatus, and in 
the extension of the specialization to all parts of the plant, 
Thayeria has gone so far beyond any other ferns, or any other 
plants whatever, that I believed, and believe, that its recogni- 
tion as a distinct genus is justified and advisable, though on 
vegetative characters alone. 
Diels * reduced Baker’s Polypodium nectariferum to Drynaria, 
and van Alderwerelt * did the same with Thayeria Cornucopia. 
Both authors seem to have failed to grasp the characteristics of 
the plants of which they were treating; and their placing these 
plants in Drynaria is unjustified even with such light as they 
had, while both of them place Aglaomorpha meyeniana, which 
they knew to agree in fructification with Polypodium nectari- 
ferum, in Polypodium, and maintain Dryostachyum as a distinct 
genus. Aglaomorpha is decidedly nearer Dynaria than is 
Thayeria. Van Alderwerelt has even included in his Section 
Thayeria a real Drynaria. 
Thayeria was first collected fertile in the Philippines by 
Ramos, Bureau of Science 7192, in Abra, in northern Luzon. 
In 1910, I collected copious fruiting specimens on Mount Santo 
Tomas, in Benguet. These showed that the Luzon plant was 
distinct from that of New Guinea, with which it had been 
identified.® As the Zamboanga plant had been made the type 
of the genus, I immediately made another attempt to find its 
fruit but was again unsuccessful. Accompanied by Mr. Merrill, 
I went for it a fourth time in November, 1910. After we had 
hunted along the entire ridge where it is common sterile, and had 
'Naturlichen Pflanzenfamilien P: 330. 
‘Bull. Dept. Agr. Indes Neerland. 21 (1908) 8. 
® This Journal 6 (1911) Botany 140. 
