b THE PEENS AND 



sorus and its involucre, as it occurs in another species — viz., L. 

 hanksii — is shown in PL II. fig. 86.) So closely do the recurved 

 margins of the pinnae and their included capsules come to each other, 

 that all trace of the venation is hidden ; but it is on the extremities 

 of the closely-approximating veins that the sori are placed. The 

 spore-capsules and their contained spores are so similar in general 

 appearance in the three ferns chosen, that we need not here refer to 

 them again. 



Our third example, Asplenium hvXbiferwm (fig. C), differs from 

 both of the others in many points, and agrees in many others. 

 Owing to the great size of the specimen selected, only a portion of 

 the frond — which when complete was nearly 3 feet long — has been 

 represented on the frontispiece. The rhizome is short and thick as 

 in the Lomaria, and more or less scaly, while the fronds stand in a 

 tuft at its apex. In them there is not. the same separation into 

 sterile and fertile, but all are nearly similar, and when mature are 

 spore-bearing. And here we may note, that the young fronds of all 

 ferns have a very different mode of unfolding from ordinary foliage- 

 leaves. They are rolled up from the apex to the base in the form 

 of a crozier, and their vernation — i.e., the position occupied by them 

 while in bud — is said to be circinate. 



The mature frond is furnished with a stipes and rachis (which 

 is often dark-coloured on its upper side), but this, instead of bearing 

 pinnae, bears a secondary set of rachises, and these again a third. 

 In the upper parts of the frond, however, the secondary rachises 

 only bear leaflets. In such a frond, the secondary rachis and all 

 that it bears constitutes the pinna, the tertiary rachis and parts 

 form a pinnule, while the further subdivisions are the lobes or 

 segments. A frond with pinnules arranged along its secondary 

 rachises is 2-piiinMte or bipinnate ; if its pinnules are again cut into 

 separate parts, it is S- or tri-pinnxite ; and if still further subdivided 

 it is decompound. It is often a matter of considerable difficulty 

 deciding what term ought to be applied in. describing the extent to 

 which the division of the frond is carried, owing to the fronds 

 being cut almost to the rachises, but having these winged in many 

 cases with a portion of the lamina. Thus some ferns are said^ 

 in the " Synopsis Filicum " — to be 2- or 3-pitmatifid, which are 

 described as 2- or 3-pinnate in some other works. The rule here 



