494 INTRODUCTION TO CRYPTOGAMIC BOTANY. 



cate teeth, marked with a central line. The genus Oreas, 

 which has not yet been found in Great Britain, is founded on 

 Weissia Martiana (Hook. Muse. Ex., t. 104). The sporan- 

 gium is deeply sulcate, and red with greenish furrows ; the 

 peristome is of a deep red, and consists of sixteen transversely 

 striate teeth. At present these plants appear not to have 

 occurred out of the northern hemisphere. 



25. DiscLELiEi, Br. & Sc, Mont. 



Sporangium sub-globose, cernuous ; ring large, sub-per- 

 sistent ; calyptra subulate, dimidiate ; teeth sixteen, cloven at 

 the base. Annual, almost stemless. 



549. This tribe consists of but a single European genus, 

 combining the habit of Phascum, with the sub-globose 

 sporangium of Catoscopiuvi, and the teeth of Trematodon. 

 " During the autumn," says Mr. Wilson, " the clayey declivities 

 where D. nudum grows, are covered with the green velvety 

 thallus, which withers or becomes discoloured after the forma- 

 tion of the fruit, and very frequently falls down by the action 

 of the winter frosts, along with the sub-stratum, which thus 

 presents annually a new surface favourable for the vegetation 

 of this singular moss, which much resembles a Phascum in 

 the mode of its vegetation." See also Bot. Zeit., 1843, 

 p. 505, t. 2. 



26. Splachnei, Br. & 8c., Mont. 



Sporangium straight, with a swelling at the base, often of 

 greater diameter than itself ; leaves diaphanous, large-celled. 

 Plants generally springing from decayed wood or dung of 

 animals. 



550. This tribe contains many of the most singular and 

 beautiful species in the whole order of mosses. The enormous 

 size which the swelling at the base of the sporangium of some 

 attains (Fig. 106, d), the variety of colouring, the singularity 

 and elegance of the forms, and in some cases the unusual 

 dimensions, make the species objects of great interest. The 

 common S. ampullaceum, when growing in abundance on the 

 shallow peaty banks of some mountain stream, where the 

 cattle often resort for watering, is exceeded in beauty by 

 scarcely any Cryptogam. In Splachnum vascalosum the 



