160 The Thread-Mosses. 



considerable plenty in 1824, on declivities by ravines, on Ben 

 Lawers, Ben Nevis, and Carnedd Llewelyn, in North Wales, 

 may be found Bryum Ludwigii, or Ludwig's thread-moss. 

 Having a dioicous inflorescence, it is not commonly met with, 

 in fruit, but its bright green extensive patches are conspicuous 

 even in the barren state. Its stems are about an inch or more 

 in length, reddish above and blackish below, in colour akin to 

 the light blackish soil in which its decumbent base is usually 

 buried, having the lower faded leaves of a reddish tint, while 

 the upper are of a full bright green colour, decurrent at the 

 base, concave, rather obtuse at the apex, which is slightly 

 serrated, and more or less spreading. The fruit-stalk, slender 

 and flexuose, is about an inch long, reddish, and suddenly bent 

 below the neck of the pendulous, somewhat pear-shaped, or 

 oval-oblong, brownish capsule, which is slightly incurved, its 

 neck tapering into the fruit-stalk, its conical lid more or less 

 obture, possessing an annulus, becoming slightly constricted 

 below the mouth when dry, and having the inner peristome 

 furnished with cilia, two or three together. The barren flower 

 is compactly gemmiform, and at first terminal, but subse- 

 quently, in consequence of the growth of terminations, it 

 becomes lateral. 



Bryum pseudotriquetrum, or the Alpine hog thread-riloss, is 

 another lover of the mountain heights, frequenting wet rocks 

 and banks on the Scottish and Welsh mountains, where it 

 grows in large patches of a deep green colour, inclining to 

 purplish or blackish, with radiculose stems like those of Bryum 

 binum, from which, however, it is distinguished by the dioicous 

 inflorescence ; the leaves also are more rigid, especially in the 

 dry state, and the fruit is generally more elongated; it is also 

 more robust, ranging from one to three inches in height. It 

 ripens its fruit in July, and in all other respects the description 

 of B. binum will suffice for this. 



Akin to these two is Bryum Miihlenbecldi, Miihlenhech's 

 thread-moss, with fasciculate, radiculose, dichotomoselv- 

 branched stems, and deep red foliage. It is said to have been 

 found on moist rocks in Devonshire, but is extremely rare if 

 indigenous. It was first found by Muhlcnbeek, whose name it 

 bears, on wet rocks on Mount St. Gothard, in 1839, and differs 

 from B. alpinum in the larger, wider, more loosely-rcticulniril 

 leaves, which are also so concave and obtuse as to be almost 

 cuculate at the apex, the margin being revolute, and the colour 

 dull red, inclining to olive. The inflorescence is dioicous, and 

 its fruiting season said to be September. 



Bryum binum, or the Lowland-bog thread-moss, grows in 

 marshy and boggy places, has a synoicous inflorescence, and 

 fruits in June and July, its stems rising from half an inch to 



