(92) 



few specimens that have come under our observation, it does not seem 

 to be common. From what we have seen, it appears abundantly distinct 

 from P. plantaginea, although the varieties often very closely approxi- 

 mate. It does not appear that the colour of the present species is so 

 apt to become brown as that of the following, all the specimens that 

 we have seen being of a peculiarly pale olive green, similar to that of 

 P. tenuissima, while that of P. 2)lcintaginea is, when young, of a darker 

 olive, which soon changes to a brownish olive, and at length to a rusty 

 or dark umber brown, and when old often becomes very much infested 

 by parasites, as Ceramium rubrum, &c. 



EXPLANATION OF PLATE CLXIIL 



Pig. l.—Punctaria latifolia, natural size. 

 2. — Surface cells and sori. 

 3. — Section of frond. 

 4. — Section of sorus. 

 5. — Spores detached. All magnified. 



