AND HEPATICOLOGY OF NORTH AMERICA. 173 



HAB. Oregon, between Puget Sound and Columbia River. (United States Explor- 

 ing Expedition.) 



This species resembles, in many respects, H. crispifolium, from the same locality, as 

 described and figured by Hooker and Schwsegrichen. But the opaque subpapillose 

 leaves of the latter species, with a minute subrotund areolation, is a mark abundantly 

 distinctive. H. Oreganum is very nearly related to H. praelongum, from which it differs 

 by its larger size, its more rigid and densely pinnated stems and branches, not com- 

 pressed, its more striated longer-acuminated leaves, and by the want of a nerve in the 

 perichaetial leaves, &c. 



7. HYPNUM OAKESII, Sulliv. (Gray's Manual of Bot. p. 673) : dioicum ; caule pros- 

 trato pinnatim ramoso, ramis flexuosis compressiusculis ; foliis lanceolatis acumi- 

 natis evanidi-costatis spinuloso-dentatis ; capsula ovata gibboso-inaequali longi- 

 pedunculata, operculo conico-rostellato. 



HAB. On decayed prostrate logs, at the base of the White Mountains, New Eng- 

 land, detected by the late Wm. Oakes, Esq. 



DESCR. Planta decumbens, flexilis, viridi-lutescens, nitens, stratum laxe implexum 

 efficiens. Caulis tri-quadriuncialis, tomento radiculoso pluries dichotomo-furcato obsitus, 

 irregulariter pinnatim ramosus, ramis dissitis patentissimis subcomplanatis elongatis flexu- 

 osis attenuatis. Folia costa circa medium evanida instructa, minute lineari-areolata, plus 

 minus plicato-striata parcius rugulosa, margine reflexa ; caulina concava, lato-ovata, brevius 

 acuminata, patentia vel subsquarrosa ; ramea ovalia, longe acuminata, patenti-erecta, api- 

 cem versus spinuloso- etiam lacinuloso-dentata. Perichsetialia numerosa imbricatim con- 

 ferta, exteriora reflexo-squarrosa, interiora convoluta erecta capillari-attenuata, omnia den- 

 ticulata subecostata. Pedunculus e vaginula elongato-cylindrica tenuis, biuncialis et ultra, 

 apice valde arcuatus, in sicco superne sinistrorsum inferne dextrorsum tortilis. Capsula 

 ovata, gibboso-insequalis, ventricosa, valde pachyderma, deorsum spectans. Peristomii ex- 

 terioris dentes lineari-lanceolati dense articulati, interioris cilia lanceolata carinata, ciliolis 

 binis interjectis. Annulus exilissimus vix ullus. Operculum conicum brevi-rostellatum. 

 Flos masculus in planta distincta gemmiformis, axillaris, 8-10 phyllus; perigonialia 

 ovata concava ecostata ; antheridia 10-12 longius stipitata, paraphysibus immixtis. 



Compared with H. brevirostre, Ehrh., its nearest congener, H. Oakesii has a subpin- 

 nate (not subfasciculate) ramification ; the branches straight (not incurved) ; leaves erec- 

 to-patent (not squarrose), oval, long-acuminate (not broadly cordate-triangular acuminate, 

 not constricted at upper end of the lamina, nor convolute at the basal angles), strongly and 



