FLORA OF BRITISH GUIANA — HITCHCOCK. 305 
The species of the forest trees are not gregarious but are scattered 
here and there. Species of the mangrove formation are gregarious 
as are also such trees as the eta palm of the swampy areas. 
In the region between the Demerara and Essequibo Rivers trav- 
ersed by the railroad connecting Wismar and Eockstone there is a 
white sand scrub similar to that found in central Florida. The soil 
is mainly a white quartz sand. The vegetation consists of shrubs 
and small trees, mostly not over 12 to 15 feet tall, growing in scat- 
tered clusters or small thickets with areas of bare sand intermixed. 
The herbaceous plants are comparatively infrequent and incon- 
spicuous. 
In reviewing the lowland flora of British Guiana in comparison 
Avith that of the United States one notices the absence of some 
families, the small representation of some, and the large representa- 
tion of others. The grasses, sedges, and leguminous plants are 
present in about the same proportion as in the United States. Some 
families common in the United States are absent or represented by 
only a few species, such as the amentiferous trees (oaks, birches, 
hickories), Eanunculaceae, Rosaceae, Saxifragaceae, Menthaceae 
(Labiatae), Scrophulariaceae, Brassicaceae (Cruciferae), and 
Apiaceae (Umbelliferae). The Asteraceae (Compositae) the larg- 
est family in the United States is represented by proportionately 
greatly reduced numbers. Some familiar families, such as Euphor- 
biaceae, are found in British Guiana chiefly as trees. There are 
arboreous species of Solanum with flowers very similar to those of 
the common white potato {Solanum tuberosum) . 
On the other hand, certain families sparsely represented in the 
cooler parts of the United States are found in greatly increased 
numbers, such as Rubiaceae, Lauraceae, and Sapotaceae. The great 
families Melastomaceae, Myrtaceae, Phoenicaceae (Palmae), and 
Piperaceae extend only into the warmer parts of the United States. 
Araceae, represented in the north by such puny plants as Jack-in- 
the-pulpit and skunk cabbage, are found as giants with leaf-blades 
2 to 4 feet long or as great climbers of the forest. The orchids do 
not reach their greatest development in the lowlands but are a con- 
spicuous feature of the vegetation around Roraima. 
It is hoped that botanists may investigate the interior, for there 
is no doubt that the central and southern parts of the colony will 
yield many interesting discoveries. 
