356 MUSCI PEiETERITI. 



apiculatis; capsula brevi-cylindrica, collo mediocri, sicca vacua 

 suberecta omnino estriata. — This plainly belongs to neither of our 

 subspecies, and is perhaps worthy to form the type of a third, in 

 which would be included the varieties (1. tenellum and e. myurum of 

 Schimper. The same author's vars. y. laxum and S. densum may 

 possibly belong to the subspecies sulcatum, but as no hint is given 

 of the capsule ever being striated, although such capsules exist 

 among Bruch's specimens, I fear lest Schimper may have (wrongly) 

 placed all such striated capsules to the credit of PL sylvaticum. 



I have fine specimens from the sides of streams in the Mourne 

 Mountains (Ireland) of "the tall mountain form, 'Eng Bot.,' 

 t. 1260, growing in dense patches, with tall erect stems" (Wils. l.c.) f 

 and they accord in all particulars with the subspecies sulcatum. 



I have said little thus far of the form of the leaves, for in both 

 subspecies they are normally ovate-lanceolate, rather abruptly 

 apiculate or acuminulate, and always acute at the very point ; and, 

 in both, the same variations occur in the degree of reflexion of the " 

 margin, the length of the nerves, and the rare presence of subapical 



teeth. But I have navar RPP.n n/nv fnrrn nf PI /7/w fiVi/ 7/7 f ?/ m 



with 



8. obtusifi 



more or less obtuse, slightly concave," which he considers the same 

 as Turner's var. y. obtimfolium and the Hyp. Donianum of 'E. Bot./ 

 t. 1446. I have not the 'E. Bot.' figure at hand, but Turner's 

 figure is far more like H. palustre than H. denticul atum , and so is his 

 description: — "Foliis arete imbricatis obtusis mediotenus obsolete 

 xminervibus" ('Muse. Hibern.,' 146, t. 12, f. 2). Yet Wilson had 

 Turner's herbarium to aid him, and must have seen the original 

 specimens of this moss. The "Plagiotheciwn Donianum" of Mitten's 

 1 Musci Austro-Americani ' is surely something very different, for it 

 has "folia subacuminata " and "operculum acuminatum" ; such as 

 the author attributes also to H. denticulatum, of which it can 

 scarcely be more than a variety. 



In general, hooked leaves and hooked capsules go together in 

 those forms of PL den ticula turn where either feature exists, and 

 the subspecific aptychus may correspond to Lindberg's PL denticu- 

 latum, var, secundum, "foliis suis plus minus secundis vel sub- 

 hamatis, haud minus in memoriam formus tenuiores Stereodontis 

 viridis referens." (Contrib. ad fl. crypt. Asia* boreali-orien talis, 

 p. 278-9); but his var. crispatidum, " robusta et foliis leviter 

 undulatis vel crispatulis " (7. c.) cannot well be our sidcatum, or he 

 would not have failed to notice so marked a feature as the furrowed 

 capsule. And if there should exist in any herbarium a Plagio- 

 thecium with dioicous inflorescence, and with the other characters 

 assigned to PL syhaticum by Wilson and myself, except that the 

 capsule is furrowed, and not smooth, I have no doubt the bene- 

 volent possessor will produce it, and thus enable us to decide 



distinct species. 



form 



I add an account of two remarkable varieties of PL sylvaticum. 

 Plagiothecium sylvaticum (Dill. L.), var. succulentu 



Wilson 



jm (Wils.) 

 larry, and 



