PEsSIN: EPIPHYLLOUS PLANTS OF JAMAICA 18 
a careful study of epiphyllous plants would throw some light on 
the origin of parasitism, such as that of leaf-infesting fungi. 
SUMMARY 
. Epiphyllous plants of diverse selected regions in Jamaica 
were ase in the field and collected for laboratory study in 
Baltimore. 
2. The results of the field observations were tabulated so as 
to give at a glance a general idea of the distribution of these 
epiphyllous plants in relation to the altitude, average temperature, 
and average humidity of their various habitats. 
3. The possible modes of attaining the epiphyllous position 
are: 
(a) Continual growing forward and dying off below, of hepatics 
and mosses, until they reach and cover the leaf. 
(6) By distribution of spores, gemmae or seeds through the 
agency of rain and wind. This is especially true for algae and 
fungi. 
(c) Propagation by displaced fragments af mature lichens, 
hepatics, and mosses. 
. An abundance of humidity, gistoraie temperature, and a 
raletivaly calm atmosphere encourage an otis epiphyllous 
growth. 
\ 5. Histological studies of epiphyll-bearing leaves of Elapho- 
glossum latifolium, Clusia havetioides and Mangifera indica revealed 
no apparent penetration of — leaf by any part or organ of the 
epiphyll. 
6. The rhizoids of epiphyllous hepatics are especially adapted 
for the epiphyllous habit by becoming thickened, by flattening 
out and by being pressed into the cuticle of the leaf, thus firmly 
attaching the epiphyll to the leaf and preventing its being blown 
or washed off easily. 
7. It is conceivable that the shade produced by the epiphyll, 
the accumulation of the organic material, the possible excretion 
of acids and other substances by its rhizoids may, have some 
physiological effect on the supporting leaf. | 
8. A careful study of the epiphyllous mode of life will, it is 
believed, bring out some close relations between parasitism and 
