324 ON SOME BRITISH MOSSES 
and Osirya ; but the employment of all such comparisons, it need 
hardly be said, requires the greatest caution. 
Explanation of Plate LXXII. 
Fig.C 1 represents the normal arrangement of axis (a), leaf, and axillary bud (a f )- 
Fig. 2 represents the condition in the monstrosity in P. Laurocerasus described 
in the text, a' cfc' = the two axillary buds. 
Fig. C 3 represents the more common mode of fission of a leaf, where the result- 
ing laminae lie in the plane of the primary lamina. The converging dotted 
lines indicate the greater or less coalescence below of the two halves of the 
fissiparously divided leaf. 
A FEW NOTES ON SOME BRITISH MOSSES ALLIED 
TO TORTULA FALLAX, Iledwig. 
By William Mitten, Esq., A.L.S. 
Having recently gathered fruiting specimens of Tortida vinealis, p 9 
1 Bryologia Europaea,' in North Wales, my attention has been recalled to 
the very considerable differences existing between it and the typical form 
so common in Sussex, on walls, and also to the confusion which ap- 
pears to me to exist among some other closely allied Mosses. 
The group of species of which Tortula fallax may be taken as the 
representative — it being the oldest described species — includes a number 
of Mosses found almost exclusively in the temperate and cooler regions 
of the earth ; they appear to be generally distributed in Europe, and 
are continued from the Mediterranean region and northern Africa into 
northern India ; a few peculiar species are found in the higher regions of 
the Himalaya; in America the preponderance of species appears to be 
on the western side of the Continent ; a few, common also to Europe, 
occur in British North America, but it is remarkable that only one 
species is enumerated by Sullivant as found in the United States. 
All the Mosses referable to this group are conspicuous from their 
tendency to become of a deep or rusty-brown colour, only the younger 
leaves being green ; in their habit, in the structure of their leaves, in- 
florescence, and fructification, there is the closest resemblance amongst 
the species ; the peristome is in some shorter than in T. fallax, but is 
precisely of the same structure, and differs only in its length and twist- 
ing ; in two exotic species it is absent. 
In Britain these Mosses are, for the most part, called Torltdas, but 
