(84) 



the branches are short and excessively divided, in others they are few, 

 long, slender, and often simple. The structure* of the frond is cellular, 

 the cells growing gradually smaller towards the cii'cumference, roundish 

 polygonal ; when young it is quite solid, but when old is traversed by a 

 very slender tube. Substance cartilaginous, scarcely adhering to paper 

 until after long steeping. Fructification, forming roundish, hemispheri- 

 cal, or elliptical wart-like tubercles over the whole surface of the frond, 

 giving it a rough and warted appearance, even to the naked eye. 

 The warts are composed of clavate, monilifonn filaments, to the base of 

 which are attached by their apices obovate spores, surrounded by a 

 pellucid limbus. Colom-, a pale yellowish brown. 



This singular plant was imtil lately a congener of Sporochmts pedun- 

 culatus, a species to which the present has some resemblance ; but it is 

 too unimportant to allow of their associating well together under the 

 modern hau--splitting ideas of classification. Both the structure of the 

 plant and the mode of fructification are considerably different. 



The fniit is generally produced in great abundance, as we have never 

 seen specimens without, and is scattered very closely over the whole 

 surface of the frond. 



It seems rather an Irish than an English species, and is not of 

 frequent occmTence in Scotland. In Ireland it is said to be not 

 uncommon all round the coast, but in England has only been found 

 on the extreme southern shores, where, however, it is common ; the 

 only English specimens we have seen are from Falmouth Bay, where 

 they were collected by Miss Warren, 



EXPLANATION OP PLATE CLIX. 



Fig. \.—Stilop1iora rhisodes, natural size. 

 2. — Portion of a branch with sori. 

 3. — Transverse section of same. 

 4. — Section of sorus. 

 5. — Spore. 

 6. — Surface cells. All magnified. 



