736 FILICES. 



sisting mainly of phosphates, carbonates, and sulphates of calcium and 

 potassium, together with silica. 



Uses — The ethereal extract has been prescribed for all kinds of 

 intestinal worms ; but recent experience goes to prove that its effects 

 are chiefly exhibited in cases of tapeworm. It is equally and thoroughly 

 efficacious in the three kinds respectively termed Tcenia solium, T. 

 medio -cannellata and Bothriocephalus latus. 



Substitution — The rhizomes of Asplenium Filix foemina Bernh., 

 Aspidium rnontanum, Vogl. {A. Oreopteris Sw.) and A. spinulosuon 

 Sw. may scarcely be mistaken for that of A. Filix Tnas. The best 

 means of distinguishing them is afforded by transverse sections of 

 the leaf-bases. In Filix mas, the section exhibits 8 vascular bundles, — 

 in the other ferns named, only 2, — a difference easily ascertained by 

 examination under a lens. Practically, no other indigenous fern than 

 A . Filix mas affords a rhizome of sufficient bulk so as to be 

 remunerative. We are not acquainted with that of the American 

 Aspidium marginale Swartz, the section of which shows 6 vascular 

 bundles ; its extract is stated by Cressler (1878) to be perfectly active. 



