GRIMMIACE^;.] 41 [Grimmia. 



Rhacomitrium heterostichum Var. y. gracilesccns BR. SCH. Bry. eur. fasc. 25 28, p. 9, 

 p.p. (1845). WILS. Bry. brit. 168 (1855). SCHIMP. Synops. 232, p.p. (1860), 2 ed. 277. 



Grimmia heterosticha Var. y. gracilesccns C. MUELL. Synops. i, 808, p.p. (1849), Deutsch. 

 moos. 368, p.p. (1853). 



Rhacomitrium obtnsum LINDB. in Act. soc. sc. fenn. X, 542 et 553 (1875). 



Grimmia obtusa LINDB. Muse, scand. 29 (1879). 



Dioicous ; short, densely pulvinate, i ii in. high, yellow green 

 above, fuscous at base, with straight erect branches, very shortly 

 ramulose. Leaves erecto-patent, straight, ovate-oblong, gradually very 

 acute, with the tip obtuse and always quite free from a hyaline point, 

 deeply carinate, margin narrowly revolute, not incrassate. nerve flat 

 and ill-defined, channelled in front, vanishing below apex ; cells very 

 smooth unistratose, nearly all rectangular, strongly sinuose and 

 crenate, narrow, a few at basal angles quadrate. Seta short, pale 

 fuscous, caps, oblong, narrowed at the mouth, glossy, fuscous, annulus 

 thick, triple, lid half length of caps., erect, acicular, straw-colour, 

 purple at base ; calyptra mitrseform with a papillose beak ; peristome 

 pale red, minute, irregular, fugacious, teeth with two unequal legs, 

 filiform, not trabeculate. Male plant more slender and branched, infl. 

 gemmaceous, bracts obtuse, apiculate. 

 HAB. Damp granite rocks and walls. Fr. 3 5. 



Snowdon (Dillenius). Llanberis, Dolbadarn castle (Hunt 1865). Tyn-y-G roes and Dolgelly 

 (Holt 1885) ! ! Luggielaw and near Dublin (Orr, 1855). Lough Bray (Lindberg 

 1873) ! ! Shanslieve, Slieve Donard, Slieve. na-Maddy and Slieve Bignian, Co. Down 

 (Lett 1884) I ! Ben Lawers (Holt 1880) ! ! Ullock, Keswick (Rev. y. Kidson 1888) ! ! 



Var. p. subsimplex Lindb. 



Stems slender arcuate, ascending, naked below, with a few simple 

 arcuate, comose-leaved branches. Leaves shorter, more obtuse, with the 

 margins more widely revolute. 



SYN. Rhacomitrium obtusum ft. subsimplex LINDB. op. c. 543. 

 HAB. Glendough (On 1870, named R. lanugitwsum). 



This moss seems quite distinct in the rounded obtuse points to the 

 leaves, which do not show any trace of a hyaline tip, even in the youngest 

 leaves. It may be known from G. aquatica and fasciculans by its small size, 

 independent of other characters. M. Corbiere finds it also at Cherbourg. 



G. affinis comes nearest to G. oblusa, but has always some leaves with 

 hyaline points, and they are also narrower and more acute at upper part, 

 and the cells smaller and less crenate. 



33. GRIMMIA AFFINIS (Schleich.) Lindb. 



Dioicous; yellowish-green, scarcely hoary. Stems slender elongate, 

 fasciculate-branched. Leaves lanceolate-acuminate, acute with a short 



