BRYUM. 339 



Hab. Rocks by water ; R. Usk, Monmouth ; R. Grwyne, Brecon. Both 

 sterile. Fr. spring. 



A Mediterranean species, intermediate between B. alpinum a.ndB. Miihlenbeckii ; 

 the leaves wider and more obtuse than in the former, with wider cells ; less obtuse 

 and cucullate than in the latter, and with narrower areolation. It is also of a paler 

 colour than either. It is probable that it should be ranked as a sub-species of one or 

 the other. 



29. Bryum Muhlenbeckii B. & S. (Tab. XLV. K.). 



Resembling B. alpinum but more slender, paler and less 

 deeply coloured, olive green, tinged with red. Leaves wider, 

 ovate and elliptic, with the apex obtuse or obtusely apiculate, 

 strongly incurved and cucullate, nerve stout, vanishing in the 

 apex; cells widely hexagonal, much laxer than in B. alpinum. 

 Capsule oblong-pyriform, small, reddish brown. Dioicous. 



Hab. Wet places in mountains, rare. Fr. late summer. 



A very distinct species, not found in fruit in this country ; but well distinguished 

 by its superficial resemblance to B. alpinum, but with broad, obtuse, cucullate leaves 

 with much looser areolation. 



30. Bryum Mildeanum Jur. (Tab. XLV. L.). 



Resembling Bryum alpinum var. viride. Tufts swollen, 

 soft, pale green, bright or shining, brown or red in the interior ; 

 stems slender, red below, 1-2 inches high. Leaves sub-equal, 

 very concave, lower widely oval-acuminate, upper narrower, 

 elliptic -oblong, gradually acute or slightly acuminate, erecto- 

 patent, less crowded than in the above-mentioned plant and 

 smaller, erect and appressed when dry ; margin widely reflexed 

 or revolute, plane at apex, entire or obsoletely denticulate at 

 point, nerve strong, red in the older leaves, yellowish in the 

 upper, excurrent in a stout straight mucro. Areolation much 

 ■wider than in typical B. alpinum, and distinctly wider than in 

 the var. viride, especially in the lower leaves ; hexagonal- 

 rhomboid, thin-walled. Capsule purple-red, clavate-pyriform. 

 Dioicous. 



HAB. On rocks and among sand in and near mountain streams ; rare. Fruit 

 very rare, not found in Britain, ripening in late summer. 



This plant comes very near to the green, laxer-leaved form of B. alpinum, and it 

 is quite possible that it may eventually have to be classed as a sub-species of that 

 plant. I have, however, found the two growing closely intermixed, almost indis- 

 tinguishable even with the lens, yet under the microscope retaining their characters 

 constantly. B. alpinum almost always shows some slight trace of red on the nerve 

 and margin at least of some (even among the upper ones) of the leaves, which are all 

 of nearly equal width ; and in the var. viride the lower part of the stem, as well as 



