o58 PROCKEDINGS OF THE ACADEMY OF [Nov., 



Jolia L., p. perfoUata L., Aristolochla arborescens L. , Entada 

 scandens Benth., Philodendron laceriim Schott. and Vitis carihosa 

 D.C. 



Savanna Vegetation. — The green covering of the open park- 

 like areas, or savannas, consists of grasses and other herbaceous 

 plants. The grasses are of most interest from an economic stand- 

 point and should be mentioned first. The following seem to be 

 the chief components of the grassy stretches of savanna land: 

 Paspalum platycaule Poir, P. distichum Linn., P. virgatum Linn., 

 P. panieulatum Linn., Chloris ciliata S\v., C. crudata Sw., C. 

 barbata Sw., Panicum colomim Linn., P. maximum Jacq. , P. 

 hirsiduvi Sw., Andrcpogon saccharoides Sw., A. gracilis Spreng.^ 

 A. fastigiatus Sw. , A. bicornis L. , A. leucostachys H. B. and K., 

 Eragrostis ciliata, with herbaceous plants, Desmodium axillare 

 D, C. and Boerhaavia erecta Linn. 



Epiphytes. — The large trees, such as the figs, the mahogany, the 

 silk cotton, are loaded down with a considerable number of 

 epiphytes belonging to the orchid, fern, cactus and aroid families. 

 Foremost among these air-dwellers are two members of the natural 

 order Cactacese, viz., Cereus triangularis Mill and Bhipsalis cas- 

 sxjtha Gaertn., which live in the crotches or attached to the upper 

 side of the limbs of tropical forest trees. Here are seen, also, 

 Philodendron laccrum Schott., Polypodium aurenm L., Vittaria 

 lineata Swartz, species of Epidendrum, and the following plants of 

 the genus Tillandsia : T. angustifulia Sw., T. complanata Benth., 

 T. biilbosa Hook., 1\ compressa Bert., T. excelsa Griseb., T. 

 fasciculata ^w., T. fiexuosa Sw., T. fe.ca Griseb., T. pruinosa Sw., 

 T. setacea Sw., T. usneoides Linn. 



The aerial life, therefore, seems to be of incontestible value to 

 these plants. Here they are installed in a position which offers the 

 largest amount of sunlight, and this advantage of increased 

 illumination seems to outweigh any disadvantage which the species 

 might have in running a constant risk of death by desiccation. 



Parasites. — There are a number of true parasites to be found 

 attached to and living upon the trunk and limbs of various tropi- 

 cal forest trees. Parasites of the genus Phoradendron, with 

 rounded or four-cornered stems, opposite or whorled, palmately 

 veined, leathery leaves, are among the most prominent. The 

 following species of the genus have been recorded as occurring in 



