32 HISTORY OF BRITISH MOSSES. 



forming a natural division into lateral and terminal fruited 

 genera^. 



The seta is circular, more or less smooth on the surface, 

 and of firm consistence, to support the weight of the cap- 

 sule. Crowning the summit of the seta is the capsule itself, 

 though there are some genera and species in which we find 

 an intermediate body — the struma or apophj'sis — resem- 

 bling in form, but more solid than the capsule ; and though 

 its use in the economy of the plant cannot be well guessed 

 at, it is, as in the genus Splachiimi, of importance in fram- 

 ing specific distinctions. 



The capsule itself varies in size, form, and consistence, 

 and is composed externally and internally of different parts. 

 In some genera it is large in proportion to the other parts 

 of the plant, while in a great many it is minute and incon- 

 spicuous. Its direction varies much, from perfectly upright 

 to all degrees of inclination, in different genera. When 

 mature the capsules of some species of Grimmia bury them- 

 selves among the foliage, probably a provision of nature to 



* Dr. Lankester, in the 'Annals of Natural Histon-,' vol. iv. p. 362, has 

 described the ciu-ious hygroscopical pi'operties of the seta of Fuvaria hygro- 

 metrica, which turns from right to left or left to right, according as it is 

 moistened at the top or bottom. This doubtless arises from the nature of 

 the lengthened spiral cells. 



