8 MR. W. MITTEN ON THE CRTPTOGAMIC FLORA 



cellulis parvis ovalibus inter se remotiusculis laevibus, perichsetiali- 

 bus elongatis erectis late lanceolatis acuminatis superne serrulatis, 

 nervo in apice evanido, theca in pedunculo gracili subunciali rubro 

 apice curvato breviter ovali aequali, collo nullo, operculo conico acu- 

 minato, peristomio dentibus luteis subulatis, processibus subaequilon- 

 gis carinatis perforatis, ciliis tribus appendiculatis interpositis in mem- 

 brana ad £ dentium longitndinis exserta. 

 Hab. Madeira, near Funehal, 185/, Johnson. 



Habit similar to the preceding, but not so rigid nor of so dull 

 a green colour. Ramification less stiff ; and some branches are 

 produced as if they had grown in a subpendulous manner. The 

 leaves are not subulate ; the nerve wider, and vanishing consi- 

 derably below the apex. 



L. setigera, sp. nov. Habitu L. spinosce, foliis patenti-secundis ova- 

 tis concavis, marginibus minute crenulatis, nervo crasso compresso 

 viridi excurrente folii longitudinem triplo superante laevi, cellulis par- 

 vis ovoideis basi paucis longioribus. 



Hab. Madeira, 1862, Johnson. 



In aspect entirely similar to L. spinosa, but in the few stems yet 

 seen less distinctly pinnate, although forming the same tree-like 

 branches. The great length of the firm and stout green nerve is 

 remarkable. 



The species composing this group, and including the Hypnum 

 hispidum, Hook. f. et Wils., are here placed as a section of Leskea, 

 that being the oldest name under which certain species having the 

 structure and habit of L. polycarpa, Ehrh., were distinguished from 

 Hypnum, and, like most of the earlier genera, established upon peri- 

 stomial characters only. But with an extensive series of species 

 it becomes evident that the most perfect form known amongst the 

 mosses having the same areolation and mode of growth is found 

 in L. tamariscina (Thuidium, Schimper), notwithstanding the ap- 

 parently different habit and ramification ; for in this species the 

 peristome has the same development as in the most complete 

 forms of Hypnum and Bryum ; and diverse as L. polycarpa looks in 

 imperfect specimens, when examined in favourable situations it is 

 found to produce occasionally free stems which in ramification and 

 appearance closely resemble L. abietina {Thuidium, Schimp.) ; and 

 from this last species the transition into the more branched forms 

 is so easy when even the allied European species are compared, 

 that M. Schimper has not ventured to separate it from his Thui- 

 dium. And as to the peristome of Leskea, taking for example again 

 L. polycarpa, it will be observed that it does not differ in structure 



