134 GRIMMIACEiE. 



Hab. Dry rocks in mountain districts ; very rare. Arthur's Seat. Nr. Kendal. 

 Fr. spring. 



Although very different from the next species in the fruiting characters, this plant 

 so much resembles it in the foliar organs that it is very difficult to point out any 

 characters by which they may certainly be distinguished in the barren state. The 

 gradual narrowing of the leaf apex is by no means to be relied on, as leaves are often 

 found quite as obtuse as in G. crinita. Almost the only useful character is the nerve, 

 which in that species is less thickened in the upper part, and is distinctly prolonged 

 beyond the apex of the lamina into a more or less terete, hardly denticulate hair ; 

 while in the present plant the hyaline point is more or less uniform throughout, toothed, 

 with the nerve not distinctly excurrent in a terete piliform hair. G. crinita is also found 

 in laxer patches, often confluent, of a more uniform grey colour from the long hairs, and 

 it is a southern, lowland plant, while G. anodon is a more alpine plant, growing in 

 smaller cushions of a darker tinge. 



4. Grimmia crinita Brid. (Tab. XXI. H.). 



In close tufts or patches, grey with the hoary leaf-points, 

 short, but somewhat variable in length. Leaves resembling those 

 of the last species, obtuse, the upper broad and concave, obovate, 

 suddenly hair-pointed, the upper part of the elongate point terete, 

 smooth, piliform, consisting of the longly excurrent nerve. Seta 

 longer, capsule less ventricose, oval, faintly striate, brown ; 

 calyptra rather larger, cucullate ; lid obtusely conical ; peristome 

 teeth lanceolate, cleft into two or three divisions which are often 

 more or less coherent. 



Hab. Dry calcareous walls or mortar ; very rare. Near Hatton, Warwickshire 

 (Bagnall). Fr. spring. 



Differs from the last in the more highly developed peristomate fruit ; and in the 

 long smooth arista formed by the excurrence of the nerve, the distinction of which 

 from the rest of the hyaline part is best seen when a leaf is doubled along the nerve 

 and viewed laterally. 



In the regions of the Mediterranean where it flourishes best it forms extensive 

 velvety patches resembling a mouse-skin in appearance. 



C. EU-CrRIMMIA. 



Capsule exserted, on a straight or arcuate seta, regular. 

 * Seta arcuate. 



5. Grimmia incurva Schwgr. (G. contorta Schp., Syn.) 



(Tab. XXI. I.). 



In short, dense, rounded cushions, deep green above, blackish 

 below. Leaves strongly twisted when dry, longly linear from a 

 narrow lanceolate base (about one line long),* with a very short, 



* N. B. — The measurements of the length of the leaves are exclusive of the hair- 

 points. 



