Fig. t,^. Haunt of the Filmy Fern. Jamaica, B. W. I. 



THE FILMY FERXS (HYAIEXOPHYLLACE.F:), 



By Winifred J. Robinson, 

 Vassar College. 



The delicate maiden hair, the fragile woodsia, the slender 

 bladder-fern seem to ns as exquisite as possible in the way of 

 fern structure, but nothing in our northern latitude can compare 

 in delicacy with the filmy ferns which are represented by one 

 species in the southeastern part of the United States and by 

 numerous species in the tropics and sub-tropics. 



In size they vary from Tricliouiancs piisilliim, which is less 

 than half an inch long and bears but one sorus, to Tricliouiancs 

 scandens, which is about eighteen inches long. They are only 

 one layer of cells in thickness, except at the veins, which gives 

 them their peculiar filmy character. Whether they have the light 

 green color of Hyuicnophyllnin asplcnoidcs, or the dark green of 

 Tricliouiancs rigidiiui, or the rusty bronze of Hyuienophylluin 

 lauosiiui, they form an exquisite drapery upon the trunks of trees 

 oi the banks of humus, where their short, wiry stems are buried. 

 There are a hundred upon the trees to one upon the ground, but 

 some of the more hardy may be found upon limestone rocks. 



