Bkown. — On the Genus Orthotrichum. 427 



lanceolate, obtuse, concave. Margins entire, plain. Nerve 

 ending below the apex. Leaves all very similar in outline, 

 lower ones small, becoming larger upwards. Areola puncti- 

 form, lower oblong. Leaves when dry erect, and slightly 

 twisted. Perichcetial leaves large, erect, ovate-lanceolate, 

 a^ute, concave. Margins entire, plain. Nerve ending below 

 the apex. Fruitstalk short, erect. Capsule small, pyriform, 

 immersed, tapering into the fruitstalk. Peristome single, 8, 

 bigeminate, perforated on the middle line towards the base. 

 Operculum convex-rostrate, about one-third the length of the 

 capsule. Galyptra mitriform, covering the capsule, plicate, 

 pilose. Male inflorescence gemmaceous in the axil of a leaf 

 below the perichaetium. 



Hab. Limestone rocks, Broken Biver, near Castle Hill ; 

 November, 1889. Collected by B. B. 



Remarks. — The outline of the capsule of this plant closely 

 resembles the figure given of the capsule of 0. crassifolium. 



5. Orthotrichum gracillimum, sp. nov. 



Plants monoecious, dark-brown below, green at the tips, 

 growing in small patches -S-in. high, branched by innovations. 

 Brandies short, fastigiate. Leaves small, densely imbricating, 

 erecto-patent ; lower ovate, linear-lanceolate, acute ; middle 

 and upper ones larger, semi-convolute, flexuous, ovate linear- 

 lanceolate, acute, sheathing at the base. Margins entire, 

 scarcely recurved. Nerve slender, keeled, ending below the 

 apex. Areola : Upper punctiform, lower small quadrate. 

 Leaves when dry slightly crisped. Perichcetial leaves erect, 

 oblong-lanceolate, acute, very concave. Margins entire, plain. 

 Nerve ending below the apex. Fruitstalk erect, about Jin. 

 long. Capsule exserted, narrow, pyriform, tapering into the 

 fruitstalk. Peristome single, 8, bigeminate, entire. Operculum 

 conico-rostrate, one-third the length of the capsule. Galyptra 

 mitriform, shorter than the capsule, plicate, pilose. 



Hab. Bocks, Mount Torlesse ; January, 1886. Collected 

 by B. B. 



6. Orthotrichum calcareum, sp. nov. 



Plants monoecious, dark brownish-green, growing in small 

 dense tufts, pulvinate, -|in. high, branching by innovations. 

 Branches closely arranged, short, ^in. long, fastigiate. Leaves 

 small, erecto-patent, closely imbricating, all very similar in 

 outline, upper ones largest, ovate or oblong-lanceolate, acute, 

 concave. Margins entire, plain. Nerve ending below the 

 apex, slightly sheathing at the base. Areola upper punctiform 

 to near the base. Leaves when dry erect, and adpressed. 

 Perichcetial leaves larger than the upper ones, erect, oblong- 

 lanceolate, obtuse, with a short hyaline apex, concave. 



