SECT. I. THE EPIDERMIS. 305 



of M. Von Gleichen upon the epidermis of Com- 

 mon Polypody and Wall-Rue, in which he thought 

 he had detected the stamens or anthers of Ferns, 

 instituted his observations upon the epidermis of 

 the same plant, and met with the same appear- 

 ances. But as he met with them in all parts of 

 the plant indiscriminately, as well as in a variety 

 of plants with conspicuous flowers, he began to 

 suspect that M. Gleichen's opinion concerning 

 them could not be correct; though he admittea 

 them to be a set of peculiar organs, of which M . 

 Gleichen was to be regarded as the original dis- 

 coverer. It is plain, however, that the organs here 

 alluded to are nothing more than the cortical glands 

 of Saussure ; with whose discoveries Hedwig does 

 not appear to have been yet acquainted. 



But the organs in question which Saussure re- 

 garde^ as glands, and M. Von Gleichen as the an- 

 thers of Ferns, Hedwig regards as being merely 

 pores, or apertures, perforating the pellicle that 

 forms the epidermis. They are contained within 

 a peculiar area, which is sometimes round, some- 

 times oval, and sometimes rhomboidal. They are 

 themselves generally oblong, though they are often 

 so much shrunk or contracted as to change their 

 form. They do not extend so far as to touch the 

 margin of the area; but in the Grasses they are 

 longer than in other plants. In their longitudinal 

 direction they follow for the mOst part the longi- 

 tudinal direction of the leaf, together with the 



VOL, i. x 



