NOTES ON WELSH HAWKWEEDS 167 



RICCIA. 



, (Frond with aerial cavities 2 



(Frond without evident aerial cavities 4 



2 'Frond linear, dichotomously forked .Jiaitans 



[ Frond not linear 3 



/Frond obcordate, longly fimbriated; or lobed and deeply sulcate 



3 J nata7is 

 I Frond flat, not sulcate, obcuueate, lobed or furcate; surface- pits 

 ( becomini? numerous crysfallina 



. jMnrgins of frond ciliated 5 



[ Margins not ciliated 7 



g (Frond green on both surfaces ciliata 



1 Frond purplish beneath 6 



g I Very small, 2-3 lines long, simple or bilobed, sulcate above ...tumida 



(Larger, furcate, broadly channelled above fflaucesce7is 



faces 8 



9 



j Frond almost four times broader than thick, attenuated towards the 



Q ] margin ; fruit scattered glauca 



Frond three times broader than thick, margins thick ; fruit clustered 

 ' sorocarpa 



Q ( Frond broadly and slightly channelled b if urea 



"(Frond deeply and acutely sulcate Pearsoni 



ANTHOCEROS. 



/Spores yellow, granulose papillate; frond nearly smooth and flat, 



^ I thick loiviH 



"j Spores black, or nearly so, spinous ; frond warty, with crisped edges, 



I thinner 2 



., f Antheridia about 2 in each cavity punctata s 



"^ I Antheridia about 20-30 in each cavity Stahleri 



„ (Frond green on both surfaces 8 



( Frond purplish beneath 9 



NOTES ON WELSH HAWKWEEDS. 



By Eev. Augustin Ley, M.A. 



HiERAciuM cALEDONicuM F. J. Haub. vai'. PLATYPHYLLUM A. Ley. 

 This plant, described by me in this Journal for 1898, p. 7, as a 

 variety of H. pollinariuui F. J. Hanb., apparently cannot be main- 

 tained under that species, but falls very well under H. caledonicnm 

 F. J. Hanb., where, therefore, I wish, with the concurrence of Mr. 

 Hanbury and Rev. E. F. Linton, to place it. It is usually easily 

 distinguished from the type by its leaves being much broader, the 

 root-leaves often cordate at the base, and coarsely toothed ; by its 

 longer branches, forming a very acute angle with the stem ; by its 

 thicker peduncles, and by both peduncles and phyllaries being much 

 more densely tomeutose. Its ligules are usually, but not uniformly, 

 sty lose. It is a very much more abundant plant in South Wales 

 than the type. 



H. vuLGATUM Fr. var. cacuminum A. Ley (Journ. Bot. 1895, 

 p. 86), described as a variety of /7. diaphanmn Fr., ought, I am 



