186 President's Address. 



fruit is, strictly speakiug, the second generation of the Moss, 

 the first being completed when the flowers are formed, by 

 the co-operation of "which tlie primary mother cell of the 

 second generation is formed, which becomes the fruit 

 rudiment, and eventually the capsule and peduncle. 



It is worthy of remark that in Ferns Mosses, and Hepa- 

 ticse, all cell thickenings occur in the second generation ; in 

 fact, what we understand by the word Fern is the second or 

 spore-bearing generation, but in Mosses and Scale Mosses 

 the sporophore is a capsule containing a multitude of free 

 cells, analogous to Fern spores. There are other modes of 

 reproduction, however, besides fruiting in Mosses, the most 

 important of which is by gemmas. The gemmae are very 

 various in form, and invariably precede the fruiting time 

 in capsule-bearing species. Among others may be 

 mentioned Didymodon gemrnascui-s. the leaves of which 

 liave an excurrent nerve, and the tips are crowded with 

 gemmae. In Tetrapliis jpeUucida the gemmae are in pedi- 

 cellate clusters in little leaf cups on proper stems (called 

 pseudopodia). In Webera annoiina the gemmae assume 

 the form of buds in the axils of barren branches, and in 

 Bryum erythrocarpum there are mulberry-shaped bulbs in 

 the axils of the leaves, that fall off when ripe. On the 

 nerve and pagina of Orthotrichum Lyelli grow strings of 

 cells, these were supposed to be of a confervoid nature, 

 hence they were named Conferva castanea and C. ortho- 

 trici. Bridel thought them glands which secreted a 

 peculiar substance ; but Schimper has demonstrated the 

 life history of this pretended Conferva, and has clearly 

 shown the gradual development into a young plant. In 

 Aulacomnium powdery masses of gemmae are sometimes 

 formed ; and the leaf points of Ulota phyllantha are thickly 

 covered with septate gemmae, while a very similar form is 

 found on the apices of Syrrhopodon. These gemmae are 

 analagous to those found on the perichaetial leaves of 

 Radula corivplanata and Jungermannia exsecta, British 

 specimens of which always have bilocular gemmae on thin 

 apices. Besides these, there are other propagating organs, 

 as the radicles on leaf apices of Leucohryura, and the stems 

 of various Dicrana, also the branched villae on Thuidium 

 Blandovii and other hypnoid Mosses. It is stated by Dr 



