R. BRAITHWAITE ON UTILISING OUU EXCURSIONS. 79 



little noticed members of our native flora, when some of us may no 

 longer be able to continue the pursuit. 



As I find species of Hepaticte are frequently confounded with 

 mosses, I have included them in the collection, and have thought it 

 might be useful to append to the specimens rough sketches of their 

 structure on an enlarged scale. 



The Hepatica? present two general forms, one frondose, resembling 

 the irregular thallus of a lichen ; the other foliose or provided with 

 leaves, and it is the latter which somewhat resemble mosses ; but 

 the leaves will almost always be found in one place, and arranged 

 on the stem distichously, or in two rows ; rarely of the symmetric 

 outline observable in mosses, but often cleft or lacerated at the 

 apex, or folded with a sacculate appendage at base. Frequently, 

 also, the stem bears at the back an intermediate series of stipule- 

 like organs named amphigastria ; the cell texture is more uniform 

 and less elongated than in mosses. Their fruit differs still more 

 from that of mosses, and affords characters for three natural 

 orders — 



EicGiACEJE, in which it is a capsule embedded in the frond. 



Marchantiace^, having capsules clustered round a stalked 

 receptacle, and bursting irregularly. 



JuNGERMANNiACE^, with a stallted solitary capsule, which bursts 

 into four valves. 



In none of these is there an included spore sac, or columella, 

 nor any trace of the lid or beautiful peristome seen in mosses, 

 but in the two latter orders the spores are intermixed with elegant 

 spiral threads, or elaters, which no doubt facilitate their dis- 

 persion. 



In touching on this topic, it is with the desire of showing that 

 this Old England is not yet so worked out, but that it may yield 

 ample store of the new and the beautiful to every earnest inves- 

 tigator ; and in directing the attention of members to some pages 

 of the great book ever open before them, let me hope that the 

 time is not far distant when the Quekett Microscopical Club may 

 become the head centre of all the field clubs in the kingdom. 



