i io ANNALS OF SCOTTISH NATURAL HISTORY 



quite unlike the large papillae of Grimmia canescens, to which 

 it can only, on other grounds, be distantly related. Besides, 

 the tufts are compact, and the stems simple or only dicho- 

 tomously branched, and have none of the nodulose ramifica- 

 tions so characteristic of Gr. canescens. A section of the 

 nerve shows it prominent behind, but flattish, with two 

 lateral obtuse angles. For purposes of reference I give to 

 this moss the name Grimmia papillulata. 



These peculiarities of structure are worthy of being 

 recorded, whatever may ultimately be the fate of the moss 

 as regards specific distinction. 



I hold, besides, that a notification of any peculiarity of 

 cell formation (and I have described several) will enable us 

 to advance to a closer appreciation of the physiology of 

 plants, and thence, probably, to a higher stage of our 

 knowledge of the life-history of mosses, etc. 



Under this heading allow me to propose to the readers 

 of these papers a problem for solution, or rather for verifica- 

 tion. The cell -formation of the pagina of Amphoridium 

 Mougeotii has lately puzzled me, and hitherto I have not 

 convinced myself of the accuracy of my observations. Each 

 cell appears to me to be connected by 4, 6, 8, or even 

 more very slender tubes with the 3 or 4 adjoining cells. 

 This is a very common mountain moss in a barren state, but 

 if any one wishes a small tuft I can readily supply him. 

 I may state that I work with a power of 370 diameters. 



I am anxious to put on record descriptions of two 

 mosses secured, in the first instance, on Ben Lawers in 

 i 864 or 1 865, which have puzzled several botanists, inasmuch 

 as each has given a different decision. For one of these 

 mosses the original station is lost, and although I searched, 

 on two subsequent occasions, elsewhere on the mountain, I 

 failed in securing another specimen. This regret is, how- 

 ever, much lessened, seeing that I picked up last summer 

 near Killin what must, in all likelihood, be reckoned the 

 perfect and, accordingly, the better developed condition. 



Hypnum provectuiu. Dioicous ; prostrate, main stems 

 often red-radiculose, sparsely divaricate -ramose, branches 

 often arcuate at the tips and radiculose and rooting there, 

 rather closely but irregularly pinnate ; leaves on main stems 



