PI. 238. 
A RUBBER-PRODUCING VINE EST THE EVERGLADES. 
(Cryptostegia grandiflora.) 
There appear to be difficulties which have not yet been overcome in the profitable cultivation of 
rubber-producing vines. The Cryptostegia has certain features about it which make it worthy 
of the attention of those interested in rubber production, and it may not be too much to hope 
that some one will devise labor-saving methods which will make the cultivation of this vine 
profitable, utilizing, perhaps, the wood pulp and the floss from the pods as secondary products. 
Since its introduction, it has become established on the keys of Florida and in the Everglades 
near Davie, where the specimen photographed was growing. It has grown vigorously, not 
being injured by flooding. Mr. Robert Werner is holding up one of the strange-shaped, nearly 
ripe pods, while just below his fingers the white latex, which is produced in abundance, is 
flowing from several incisions. The rubber of Cryptostegia, which is contained to the amount 
of 2 per cent dry weight in the twigs and leaves, is reported to be hardly equal to Ceara 
rubber, although its general qualities are encouraging. (Photographed by David Fairehild, 
Pebruary 6, 1916; P20012FS.) 
