TEICHOMANES. 177 



the next series shorter, more ovate, and the third series of 

 divisions narrow, more or less linear. The ultimate branches 

 of the veins which extend into the divisions of this third 

 series, end just at or within the apex of the lobes if they are 

 barren; but if they are fertile, they are produced beyond 

 the margin, and surrounded at the base by the urn-shaped 

 involucre, within which the spore-cases are placed. Some- 

 times the involucre is so placed as to appear immersed 

 within the margin, but it more frequently projects beyond 

 the margin. There is also considerable variation as to the 

 length to which the bristle-like receptacle is extended 

 beyond the involucre ; sometimes scarcely exceeding it in 

 length, and sometimes being four or five times as long. 



The lanceolate form of this plant has been sometimes 

 thought distinct from the broader form, but the general 

 opinion is, that it is an extreme variety of the same species ; 

 to this the name of Andrewsii is applied, in compliment 

 to the gentleman by whom it was first discovered. 



The Sister Isle now claims, so far as the British Isles are 

 concerned, sole parentage of this lovely, half-transparent 

 species. There, amidst dripping rocks, it thrives with a 

 degree of luxuriance which charms every one who has seen 

 it creeping over their shelving ledges. It is said to have 



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