Polytrichum.-} APLOPERISTOMI. 49 



P. commune and its varieties. The stems are from three to 

 four inches in height, the capsule is exceedingly variable in 

 form. In English Botany it is represented as quadrangular, 

 but far more decidedly so than ever we have seen it ; not un- 

 frequently it is ovate without any angles ; we have some speci- 

 mens, gathered on the highest summit of Ben Nevis, in which 

 it is almost exactly spherical ; and Wahlenberg has met with 

 plants having capsules so cylindrical that he mistook them for 

 individuals of P. urnigerum. The apophysis is very indistinct, 

 sometimes obsolete. Mr. Arnott thinks that the P. campanu- 

 latwn. and furcatum of ffornschuch, in Hor. Phys. Ber., are 

 hardly to be distinguished from this. 



8. P. urnigerum ; stems elongated branched, leaves erecto-patent 



lanceolate acute their margins plane serrated, capsule erect 

 cylindrical destitute of an apophysis. (TAB. XI.) 



Polytrichum urnigerum. Menzies in Linn. Trans. Turn. Muse. 

 Hib. p. 86. Smith, Fl Brit. p. 1377. Engl Bot. t. 1218. Schwaegr. 

 Suppl. v. I. p. 318. Hobson, Brit. Mosses, v. 1. n. 18. Drummond, 

 Muse. Scot. v. 1. n. 15. Hook. FL Scot. P. II. p. 126. Arn. Disp. 

 Muse. p. 71. Moug. el Nestl n. 28. Funck, Deutschl. Moose, t. 57. f 

 14. 



P. pulverulentum. Schwaegr. Suppl. v. 1. p. 322. Brid. Meth. p. 

 199. 



P. fasciculatum. Brid. Meth. p. 199. 



P. dentatum. Schwaegr. Suppl. v. 1. p. 321. Brid. Meth. p. 199. 

 P. nigrescens? Brid. Meth. p. 198. 



P. microstomum ? Brown in Linn. Trans, v. 1 2. p. 569. 

 HAB. On banks and sides of streams, principally in moun- 

 tainous countries. Mr. Turner has found it on banks at 

 Gillingham, Norfolk. 



This species has much resemblance to the following in the 

 shape of the capsule, but in its foliage approaches nearer to the 

 two preceding ones. The leaves, however, are very much more 

 acute, broader, very strongly toothed, and of a singularly glau- 

 cous green hue, (reddish only through age,) by which it may be 

 distinguished at first sight. Its stems are still more branched 

 than those of P. alpinum^ and about two or even three inches 

 in length. 



9. P. aloides ; stems short, leaves linear-lanceolate obtuse, their 



margins plane serrated principally at the extremity and at 



D 



