4 Transactions of the 



branches each of tho imbricated perigonial leaves enclosing a single 

 globose antlieridium on a slender pedicel, which is inserted at the 

 side of the leaf base. Paraphyses surround them, but instead of 

 being simple, as in mosses, they are very long, much branched, and 

 of cobweb-like tenuity. 



The perigynium of the female flower-sheath terminates one of 

 the short lateral branchlets at the side of the capitulum, and is of a 

 deep-green colour, with large sheathing leaves ; the archegouia do 

 not differ from those of mosses. 



After impregnation the fruit receptacle enlarges and extends 

 itself into a pseudopodium, on which the capsule is sessile; the 

 vaginula was thought to be absent from these plants, and hence 

 Bridel formed for them a section " Musci evaginulaii." It is, how- 

 ever, very distinct, being the disk-shaped enlargement at the apex 

 of the receptacle in which the expanded bulbous rudiment of the 

 pedicel of the capsule is completely buried. 



The calyptra, or outer cell-layer of the archegonium, has not 

 the definite form common to mosses, but is a very thin colourless 

 membrane closely investing the capsule, by the enlargement of 

 which it is torn irregularly into shreds, the lower portion being left 

 attached to the vaginula. 



The capsule up to maturity remains in the perichsetium, but 

 after that the receptacle elongates and carries it upward on this 

 pseudopodium, which does not correspond to the pedicel of a moss, 

 that being always found above the vaginula ; still, a pedicel does 

 exist in Sphagnum, but it is bulb-shaped, and enveloped by the 

 vaginula. The capsule itself is very uniform in all the species, 

 being almost spherical, the hd only slightly convex, without any 

 beak or point, and we never find any trace of a peristome. The 

 sporangium, or spore sac, does not attain the development found in 

 mosses, for it appears like a lioUow hemisphere in the interior of 

 the fruit, its outer wall being coherent with the inner cell-layer 

 of the cajjsule, its inner wall with the columella lying beneath it. 



The spores somewhat resemble those of Lycopods in being of 

 two kinds — macrospores produced by fours in a mother cell and 

 tetrahedral in form, and microspores which are more spherical, and 

 not half the size. 



With respect to the function of these plants in the formation of 

 peat, I cannot do better than quote Professor Schimper's words. 

 He says : — " Unless there were bog mosses, many a bare mountain 

 ridge, many a high valley of the temperate zone, and large tracts 

 of the northern plains, would present an uniform watery flat, instead 

 of a covering of flowering plants or shady woods. For just as the 

 Sphagna suck up the atinosplieric moisture, and convey it to the 

 earth, do they also contribute to it by pumping up to the surface of 

 the tufts formed by them the standing water which was their cradle, 



