SOME NEW GENERA OF MOSSES 101 



SOME NEW GENERA OF MOSSES. 



Bi' H. N. Dixon, M.A., F.L.S. 



(Plate oG4.) 



(The types or — where the type is indicated as elsewhere — • 

 co-types of all the plants described below are in my herbarium.) 



DlCRANACE2E. 



Nanobryum Dixon, gen. nov. 



Dioicum.^ Caules (5* et $ annui, in protonemate perenne valde 

 sparsi, minuti. Planta c? minutissima, subsessilis. Planta 2 2-8 mm. 

 alta, fructifera 5-7 mm. Folia perpauca, inferiora minuta, comalia 

 2-4, multo majora, 2 mm. longa, e basi late ovata vaginante abrupte 

 subulata, subula longa, iilif ormi, Hexuosa, e costa excurrente plerumqiie 

 composita. Areolatio angusta, e cellulis linearibus, alaribus nuUis, 

 instructa. Seta 3-4 mm. longa, tenuissima. Theca minutissima, 

 circa '5 mm. longa (deoperculata), horizontalis vel subpendula, 

 curvata, macrostoma, leptodermica ; peristomium ei nonnullarum 

 specierum minutarum Flssidentis perfecte simile, dentibus siccis 

 valde patentibus, madidis intra thecam fortiter inflexis, lamellis 

 externis dense, humiliter trabeculitis, internis pulchre alte cristatis, 

 cruribus filiformibus, spiraliter incrassatis. Calyptra ignota. 



Nanobryum Dummeri Dixon, sp. nov. 



Protonema persistens atro-viride, e radiculis ramosis atque filis 

 chlorophyllosis tenerrimis ramosis donsissime intertextis instructum. 

 Planta S subsessilis, minutissima, foliis perigonialibus ssepius duabus 

 concavis, amplexantibus, brevicuspidatis, antheridiis numerosis, tur- 

 gide ovalibus. 



Caulis fertilis paucifolius ; folia inferiora circa tria, minuta, late 

 ovata, cuspidata, concava, subecostata, integerrima ; suprema ple- 

 rumque tria (aliquando 5-Q) multo majora, rigidiuscula, suberecta 

 vel subsecunda, nitida ; e basi vaginante late ovata in subulam duplo 

 vel triplice longiorem llexuosam integram filiformem cito angustata. 

 Costa apud basin tenuis, superne valida, excurrens, partem majorem 

 subulse formans. Areolatio e cellulis ubique angustis, 8-13 [x latis, 

 superioribus linearibus vel rhomboideo-linearibus, chlorophyllosis, 

 parietibus firmis, baud incrassatis, inferne brevioribus, latioribus 

 (10-16 ju latis), parietibus tenuibus instructa; alares nuUse. 



Fl. $ terminalis, archegoniis circa 10, paraphysibus subnullis. 

 Seta tenuissima, pallida, 3-4 mm. longa. Theca minima, madida 

 horizontalis, sicca subpendula vel pendula {cf. descriptio generis) ; 

 exothecii cellulie perlaxie, subregulariter hexagono-rectangulares vel 

 isodiametricfB, angulis rotunda tis ; circa 60 /x latie, parietibus tenuibus 

 collenchymaticis ; apud orificium seriebus nonnullis rubrae, valde 

 incrassatse, transverse lineares. Spori magni, circa 50 jx. 



(Peristomium ; cf. descrip. generis.) Operculum pallidum, conico- 

 rostellatum, majusculum. 



Hab. On damp earth and in hollows of fallen trees, in forest, 



