NEW AND RARE SCOTTISH MOSSES 



103 



100. CLYDE ISLES. 

 (Rev. E. S. Marshall, I.e.) 



Rubus Rogersii. 

 R. dumnoniensis. 

 Callitriche autumnalis. 

 Arctium intermedium. 

 Gentiana baltica. 

 Euphrasia borealis. 



E. brevipila. 



E. scotica. 



E. stricta. 



Glyceria declinata, Breb. ( = G. 



plicata, var. depauperata, 



Crcpin). 



NEW AND RARE SCOTTISH MOSSES. 

 By JAMES STIRTON, M.D., F.L.S., etc. 



SINCE the publication in the number of the " Annals of 

 Scottish Natural History" for January 1899, of a more 

 precise description of Dicranum Fergnssoni, detected for the 

 second time near Carsaig, I have been fortunate in alighting 

 on a small tuft of the original gathering of this moss in the 

 Island of Mull. The exact spot is not now known, but it 

 must have been in the neighbourhood of Ben More, probably 

 on its lower slopes. In this tuft the stems are abundantly 

 covered with the red tomentum. Two years ago I picked 

 up the same moss near Tarbert in Harris in a more 

 luxuriant condition, where the red tomentum was much 

 more abundant, presenting in this respect very much the 

 aspect of D. MiiJilenbeckii. Indeed a closer inspection of 

 the two mosses reveals the fact that D. Fcrgussoni has 

 greater affinities to D. MiiJilenbeckii than to D. fuscescens. 

 In both there is abundance of osculating pores in the central 

 portion of the pagina, a little up from the base of the leaf. 

 The slender tubes connecting these pores are difficult to 

 detect in either plant, but are rarely entirely absent. In 

 D. Miihlenbeckii the teeth on the upper margins of the 

 leaves, as well as on the back of the nerve in the same 

 region, may be said to be spinuloso-serrate, but those of 

 D. Fergnssoni are blunt and distantly set, while those on the 

 nerve degenerate into mere hyaline tubercles when, indeed, 

 they are perceptible. In the former, also, the basal cells are 

 much . broader. A thin cross- section of the nerve of 



