314 THE PLANT COVERING OF OCKACOKE ISLAND. 



acteristic of the whole Austroriparian area, and abundant on the 

 mainland, scarcely 30 kilometers distant, are wanting upon Ocracoko 

 Island. Notable among these absentees are the pines (Pinus palustris, 

 P. taeda), the gums (Nyssa spp.), the bald cypress {Taocodium dis- 

 tichum), the deciduous oaks, the cane (Arundinaria macrosperma), 

 species of Erianthus, Carex verrucosa, Smilax laurifolia, and Ber- 

 chemia scandens. Hardly less striking is the nonoccurrence of most of 

 the bright- flowered herbs that abound in the pine forests on the west 

 shore of Pamlico Sound. Such are species of Coreopsis, Helianthus, 

 Lacinaria (Liatris), Eupatorium, Solidago, Rhexia, Gerardia, Hyper- 

 icum, Sarracenia, I labenaria, and Polygala. The unfavorable environ- 

 ment is doubtless responsible for the absence of many of these plants, 

 conditions upon the island being suitable only to the hardiest species. 

 Scarcity of shade, of humus, and of fresh water accounts in like man- 

 ner for the poverty of the flora in most of the lower forms, such as 

 fresh- water algae, fungi, hepaticae, mosses, and ferns. The numerous 

 arrangements by which many of the higher plants are protected against 

 excessive loss of water may also serve in some measure for protection 

 against parasitic leaf fungi, and may partly account for the com- 

 parative scarcity of the latter. 



The general aspect of the plant covering is not attractive. Bright 

 green foliage and flowers of brilliant coloring are too scarce to make 

 much impression, while, except in the salt marshes, the plants are 

 usually so scattered that it is the soil which gives tone to the land- 

 scape. Furthermore, the trees and shrubs are mostly characterized 

 by gnarled trunks, many dead branches, and ragged foliage, as a 

 result of exposure to sand-laden winds. Altogether, the picture is 

 one of somber monotony. 



LIST OF PLANTS COLLECTED AND OBSERVED. 



[The prefixed asterisk denotes that the plant is introduced.] 



LICHENES. 



Usnea barbata L. 



Ramalina montagnei De Not. 



MUSCI. 

 Bryum argenteum L. 



Rhyuchostegium serrulatuia Hedw. 



POLYPODIACEAE. 

 Asplenium platytiearuit (L.) Oakes. (A. ebeiieum Ait.) 



PINACEAE. 



Juniperus virginiana L. 



TYPHACEAE. 

 Typha latifolia L. 



SCHEUCHZERIACEAE. 



Triglochin striata Ruiz & Pav. 



