24 HANDBOOK OF BRITISH MOSSES. 



by Funaria hygrometrica, in which it is rather complicated, 

 and springs off the moment the lid bursts, each portion twist- 

 ing up spirally from within outwards. The lid itself varies in 

 form, and is either extremely short and convex, with or with- 

 out a central apiculus, or more or less elongated, being some- 

 times as long as or longer than the capsule. In most cases 

 it falls off entirely, but sometimes it is suspended at the top of 

 the dry columella, as in some Splachnece. Sometimes when 

 falling it carries with it a part or the whole of the columella, 

 as in Pottia and Schistidium (Plate 21, fig, 6 e). 



The mouth of the sporangium thus exposed by the rupture 

 of the lid, and without taking the annulus into account, is 

 either entirely naked, closed more or less perfectly with a 

 narrow membrane spreading over the spore-sac, or furnished 

 with one or two rows of more or less convergent teeth, sepa- 

 rate or connected at the base, sometimes indeed so intimately 

 connected as to form a plicate membrane variously modified, 

 according as the upper portion of the constituent teeth is more 

 or less free. The teeth are either four in number, or consti- 

 tute some multiple of four, in the less numerous cases being 

 frequently divided by lines in accordance with the general 

 rule. Sometimes though free at the base, they are connected 

 by transverse bars above, so as to constitute a network, as in 

 Fontinalis (Plate 3, fig. 2) ; and sometimes the very tips of 

 the teeth are connected so as to form a little membrane, as in 

 Funaria (Plate 16, fig. 6). 



The teeth vary slightly in their origin, being occasionally 

 more or less confounded with the annulus, or anomalous as to 

 their formation, as in Polytrichum, Buxbaumia, and Tetr aphis, 

 but as a general rule, each individual of the outer row of teeth, 

 or, as it is called, the outer peristome, arises partly from the 

 thickening of the walls, especially towards their centre, of 



