SECT. YII. SPHAGNEI. 331 



of great interest. The common S. ampullaceum, when 

 growing in abundance on the shallow peaty banks of 

 some mountain stream where cattle come to drink, is 

 scarcely exceeded in beauty by any cryptogam. Species 

 of this order are abundant in the two hemispheres, but 

 the same species rarely occur in both. Their habits, 

 too, are different, for while those in the north only grow 

 on manure, those in the south grow on the trunks 

 of fallen trees. Three genera occur in Great Britain. 

 Gemmae are found in the axils of the leaves in most 

 species of this group. 



The tribe of Schistostegei consists of but a single 

 most elegant species. It inhabits shady caverns, which 

 are sometimes lighted by a golden gleam from the re- 

 fractions of the confervoid shoots of its mycelium-like 

 pro-embryo, which is perennial, and produces a new 

 crop year after year. The urn is subglobose without a 

 peristoine, and when young the spore cells radiate from 

 the columella as in the Splachna. The leaves show 

 various intermediate stages between a vertical and hori- 

 zontal insertion, and are sometimes perfectly free, while 

 at other times they are united. This moss is scarce, and 

 confined to the northern hemisphere. 



There are various genera of aquatic mosses in the 

 different tribes, most of them floating plants. Of these 

 are the pleurocarpous Fontinalei, which inhabit the 

 northern hemisphere ; their urn, with its double peri- 

 stome of sixteen teeth, forms a beautiful microscopic 

 object, on account of the latticed work in the inner 

 row, and the cross bars on the outer teeth, which are 

 united at their tips by two and two. The common 

 species have sharp-angled triangular stems, and keeled 

 leaves which clasp the stem at their base, and are 

 sometimes cleft along the keel. 



The syncladeous Sphagnei are aquatic bog mosses 

 of a pale yellowish green colour. They form but one 



