92 BRITISH FERNS. 



different, consisting of a two-ranked spike of imbedded spore- 

 cases. There are but two native species. 



The name Ophioglossum literally means Adder's-tongue, 

 which is the English name borne by this plant. It is de- 

 rived from Greek words which mean a serpent, and a 

 tongw. 



COMMON ADDER'S TONGUE. [Plate xn. fig. 1.] 



This is the Ophioglossum vulgatum of botanists. 



It is a small stemless plant, producing a few coarse brittle 

 roots from a central crown which annually produces a bud 

 from which, about May, a new frond arises. The fronds 

 grow from six to ten or twelve inches in height, with a 

 smooth, round, succulent stipes below, and becoming di- 

 vided, in the upper part, into two branches, the one of which 

 is leafy, entire, ovate-obtuse, traversed by veins which form 

 elongated meshes. The fertile branch is erect, contracted, 

 about half its length being soriferous, forming a linear 

 slightly tapering spike of two lines of crowded imbedded 

 spore-cases. The spore-cases are considered as being pro- 

 duced on the margins of a contracted frond ; when mature, 

 the margin splits across at intervals corresponding with the 

 centre of each spore-case ? so that eventually the spike resem- 

 bles a double row of gaping roundish cavities. 



The Adder's-tongue is very abundant in the localities 

 where it is found, which are damp meadows and pastures, on 

 a loamy soil. It is generally distributed over England, but 

 is less abundant in the other parts of the United Kingdom. 

 The species is a common European plant. 



There is no difficulty in cultivating the Adder's-tongue, 

 whether in pots, or among an out-door collection of Ferns ; 

 the essentials are a stiff loamy soil, and the constant pre- 

 sence of water enough to prevent drought. 



DWARF ADDER'S TONGUE. 



The Dwarf Adder's Tongue is the Ophioglossum lusitanicum 

 of botanists. 



This species is technically distinguished by the small lan- 

 ceolate fleshy barren branch of its fronds ; and by its being 

 altogether much smaller than the common species. From 

 the crown of the rhizome the frond rises to the height of 

 about one and a half to three inches, and is divided above 

 into a barren leafy branch, and a spicate fertile branch. 

 Occasionally a barren radical frond, of lanceolate form, ac- 

 companies the two-branched frond. The barren branch is 



