io6 ANNALS OF SCOTTISH NATURAL HISTORY 



This collection, consisting of nearly forty distinct species, 

 is of considerable interest from several points of view. In 

 the first place it is decisively not a paludal or a peat-moss 

 association. I have examined bryophytic remains from 

 perhaps a dozen deposits of varying age, ranging from 

 quite recent to early glacial or pre-glacial times, and I have 

 seen reports of numerous others. In all these collections, 

 with scarcely, if my memory serves me, an exception, not only 

 has the paludal element been largely, indeed overwhelmingly, 

 preponderant, but in nearly every case any other element 

 was entirely absent, or if present it occurred in such minute 

 proportion as to suggest an accidental introduction or a 

 quite exceptional occurrence. The usual species comprise a 

 large percentage of pleurocarpous mosses, such as Campto- 

 thecium nitens, Hypna of the sections Harpidium, Calliergon, 

 etc., with a sprinkling of Aulacomnium, Philonotis, Fontinalis, 

 and similar aquatic and paludal Acrocarpi. This is of 

 course what one would reasonably expect, since these com- 

 paratively delicate, non-vascular plants would naturally re- 

 quire the conserving influence of peat, or of some closely 

 similar deposit, for their preservation. Mosses in other 

 forms of deposit would have far less chance of being pre- 

 served. 



The present collection comes as a somewhat welcome 

 relief from such associations as the above, which not only 

 repeat themselves with a monotonous frequency, but give 

 one a conception, exaggerated no doubt, of a dull sameness 

 in the configuration of these northern lands in the prehistoric 

 pleistocene periods, of unvaried peat moss, and bleak moor- 

 land and barren mountain-side. The Fort William mosses 

 tell a very different tale. There are but few of them (Dicra- 

 num Bonjeani, Fissidens osmundoides, Bryum pseudotriquetrum, 

 Hypnum undnatum, H. fluitans, H. falcatuni, and H. cnspi- 

 datuni) which could be considered in any way paludal 

 mosses ; only the last three are distinctively, and not one of 

 them is necessarily such. They are quite as frequently, 

 and some of the rest are exclusively (Hyocomium flagellare, 

 BrachytJiecium plumosum, Hypnum palustre, Blindia acuta, var. 

 trichodes\ the inhabitants of wet rocks in and by mountain 

 streams ; and it is quite certain that these latter, at least, 



