604 



FILICES*. 



which are identical in form, consists of fibrous tissue precisely 

 like that of the circumference, the inside is vascular. 



The inner plates become separate afterwards, and appear 

 to consist entirely of vascular tissue in the centre, much crowd- 

 ed, and of fibrous tissue on the circumference. The tissue of 

 the circumferential fibres is not continuous, but forms two 

 plates interrupted along towards the end of the outer lobes of 

 the inner vascular fibrous system ; the line of interruption 

 has externally the appearance of a white cord running up 

 along both sides of the stipes, near its inner angle, and suffer- 

 ing no interruption from the exsertion of the pinnae. 



The white colour of these two is singular, because they are 

 composed of the same greenish tissue, of which the bulk of 

 the stipes consists ; it does not appear to have stomata. 



The inner general plates may become confluent by the in- 

 ner lobes of their outer faces; It is from these that the 

 vascular fibrous system of the pinnae is derived. 



The pinnae have precisely the same organization, the same 

 basis of cellular tissue, the same intro-marginal interrupted 

 plate, the same inner confluent central one. 



I believe that the white lines do have stomata, although I 

 have not seen them, for they have precisely the same appear- 

 ance as to under surface of the divisions of the frond. 



In the primary veins of the pinnules the circumferential 

 plate is obsolete, if it exists, it is only partial. 



The axis has the same organization ? its bulk is composed 

 of dense white cellular tissue, surrounded by a pellucid muci- 

 laginous looking margin, I believe of a sort of fibrous tissue, 

 it contains more, or fewer plates according to its size. 



Its growth is endoginous, as every growth must be, if a 

 simple axis be assumed. 



To investigate the reproductive organs in this family, it is 

 in the first place necessary to submit the same individuals 

 to examination, marking each young frond examined, so 

 that it may be recognised in its adult state. Otherwise 

 we shall have no direct proof as to what the changes are, that 



