XXXIX] JAMESON 1 A 69 



rhizome forks : it bears alternate leaves with closely ranged pinnae of circular 

 outline, while the whole when young is covered by dense golden-brown 

 hairs that are simple and multicellular. There are no scales, but small mound- 



W fP 



Fig. 628. Jamesonia Hook, and Grev. ^ = pinna of 

 J. nivea Karst. B—E=J. ca7iescens (Klotzsch) Kze. 

 j5 = habit. C=a pinna. Z* = part of a transverse 

 section through a fertile pinna, the lower surface 

 uppermost. E — part of a leaf. (After Karsten. ) 



like outgrowths are common, on which the hairs are often seated. The upper 

 surfaces of the adult pinnae are naked, but the woolly hairs remain perma- 

 nently on the lower surface protecting the sporangia (Fig. 628, D). The 

 vascular system of the axis is a slender solenostele, in which the alternate 



