10 FLORA OF ST. CROIX AND THE VIRGIN ISLANDS. 



Interspersed bctweeu these evergreens iU'c seen ^■arious species of 

 arboreous plants with deciduous leaves, tlie nuuiljer otAvliicli, however, 

 seldom is larjj:e enough to seriously change the general aspect of the 

 forest as beinj; uuiforinly green all the year round. The time for shed- 

 ding their foliage in these forms is generally from January to April, 

 most of them, as stated before, floweriug i)recociously at this time, as 

 the moisture in the ground is not suflicient to allow them to retain llieir 

 foliage together with the producing of the flowers. It appears evident 

 that this is the reason for the shedding of the leaves, from the fact ob- 

 served by me in several species (such as Piscidia Erythrina and others), 

 that iii(li\ iduals which, from being too young or for some other reason, 

 do not tlo\ver, do not shed their foliage, but evidently find moistui'c 

 enough in the soil to resist the drought, not having to spend theii 

 resources on the production of flowers and fruits, as others of their kind. 



The most prominent among the trees and shrubs with a deciduous 

 foliage ai'c *S^>ow<?ias lutca^ SchmidcUa occidentalism the enormous Erio- 

 dcndron aii/rdctuosiim, Ilura crepitans^ Cascaria ramijlora, Sahinca jlorida, 

 and several others, which all more than the evergreens contribute their 

 share to the forming of a layer of leaf-mould under the taller forms. Yet 

 this layer is but scanty in most i)laces, and from the want of it, as well 

 as from the dense shade produced by the evergreen trees and shrubs, 

 the minor forms covering the ground are comparatively scarce, and 

 chiefly confined to some Piperacere, Acanthacea?, and Gramineae, as 

 well as a few ferns and mosses, among which Hemionitis 2)ahnata, Pteris 

 l)cduta, and As2)Ieniiim j^nf^ifJ^f^ft are the most conunon. 



A somewhat richer variety is presented by the numerous epiphytes 

 that cover the branches and stems of trees and shrubs, notwithstanding 

 tlial the baric of the latter, from the uiiilbrm teiiipcratnre, is, as a rule, 

 exceedingly smooth, and but rarely covered with lichens or mosses. Of 

 real parasites oidy a few are met with, c>ij)ecvMy Loranthus cmarfiinatusj 

 whilst the non i)arasitical epiidiytes are numenmsly represented by 

 Bromeliacea' (princijially the genus Tillandsia), Aroidea3 (among tlu-m 

 the hu'ge-leaved Philodendron gifjantcum), and Orchidacea} (chiefly Epi- 

 dendrums an<l Oncidiums), as well as some ferns. Of these latter families, 

 se\ eral s])ecies ai'e Ibund oidy on the highest ri<lges of the islands, 

 at an ele\atioji of over l.')00', there forming a Ibiniation i»cculiar to 

 these regions, comprising, among others, some terrestrial Orchids, such 

 as JTiihoiaria maculosa and alatdj as well as sonu' Aroidea*, Uronu'liaeea^ 

 and f»'rns, among wliirh the bfaiififnl Ciinflim tirhitmi deserves special 

 mention. 



