HYOPHILOPSIS, A NEW GENUS OF POTTIACE^ 141 



differs, as from the other two species, in the sHghtly larger spores, 

 and especially in the bands of the capsule, which, in the allied 

 species, are broad, wider than the intercostal spaces, and composed 

 of 4-0 longitudinal series of cells ; in 0. Griffithii they are very faint 

 and narrow, often composed (except at the extreme orifice of the 

 capsule) of one to two rows of indistinctly marked cells only, and 

 the intervals of thin- walled cells very much wider. The leaves 

 also are very different in form and texture, the margins but little 

 revolute, and the cells incrassate. 0. 2^uinilum differs in the form 

 and recurved margins of the leaves, and especially in the more 

 tapering base of the capsule. This latter character also separates 

 it from 0. microcarinim, which also has the overlapping cells of 

 the stomata scarcely protuberant. 



Orthotrichum sp. A specimen from Mitten's herbarium, 

 labelled " 209, Nubra, 11,000, 1 Sept. 1848 " in Mitten's hand, is, 

 I have very little doubt, an undescribed species. It is closely 

 allied to 0. speciosuvi, but the only matured capsule shows a 

 marked departure from that species in the structure of the capsule. 

 The exothecium cells in 0. speciosum are very regularly arranged 

 in longitudinal rows, regularly rectangular-oblong in form ; in 

 Mitten's plant these cells are irregular, both in form and arrange- 

 ment, being of various shapes, from oblong to triangular and 

 rounded. The calyptra is also quite naked, the capsule scarcely 

 striated. In view, however, of the scanty material in poor condi- 

 tion, I do not venture to describe it as new, but it is a species for 

 which a look-out should be kept among Orthotricha from the 

 higher altitudes in the Himalayas. 



0. CRENULATUM Mitt. An unnamed specimen in Mitten's her- 

 barium, labelled " Keris Shayuk Valley, Tibet, Dr. Thomson," is 

 certainly this species, mixed with Drummondia Thomsoni Mitt. ; 

 it is probably part of the original gathering. The ribs of the 

 capsule consist each of 6-8 rows of cells ; the stomata are im- 

 mersed, but the overlapping cells, instead of being very protuberant 

 and greatly hiding the guard-cells, as in 0. Simicei, are scarcely 

 prominent, and leave the guard-cells almost uncovered. The leaf- 

 cells also are more distinctly papillose. It is no doubt a good 

 species, differing in the denser shorter habit, the less emergent 

 capsules, and the narrower, more concave leaves, as pointed out 

 by Mitten, as well as in the above characters. 



A further specimen of Orthotrichum from Mitten's herbarium, 

 from the Nilghiri Mts., and probably collected by Strachey, is 

 named 0. revolutum Mitt. MS. It is very closely aUied to 

 0. anomaluin ; in fact, except that the stomata are almost entirely 

 covered by the overlapping cells, and are scattered about the 

 middle of the capsule, I can find no difference. But the material 

 is scanty and poor, the peristome much destroyed, and it is per- 

 haps best left undetermined. 



Still another plant, labelled (in a hand I do not recognize) 

 " Mungalin/'- Sept. 1887, alt. 1000' ; only a fragment on a schist 



* ? Mungaliri ; the writing is indistinct. I have not been able to trace this 

 locality. 



