20 T. Holm — Studies in the Cyperaeeoe. 



many, e. g., all the broad-leaved species of Fanicum, viz : 

 F. microcarpon, viscidwn, clandestinnm, etc. We have 

 already described the structure of the inflorescence and of the 

 single flowers, and having not observed any other characters of 

 morphological interest, we will proceed to the anatomical part 

 of our paper. 



The rhizome. 



This shows a very firm structure in F. scirpoidea, since the 

 bark-parenchyma contains a concentric ring of small groups of 

 very thick-walled stereome, besides that a closed ring of several 

 layers of this same tissue, the stereome, surrounds the central- 

 cylinder. The mestome-bundles seem to be all collateral, and 

 are supported by stereome on their hadrome-side ; they are not 

 arranged in any order, but scattered in the large mass of funda- 

 mental tissue. We mentioned in our previous article upon 

 Dulichium the presence of tannin-reservoirs, which we have 

 noticed again in both species of Fuirena. These reservoirs 

 are quite numerous in the rhizome, especially in the outer 

 layers of the bark-parenchyma. 



By examining the rhizome of F. squarrosa, the internodes 

 of normal thickness showed a large quantity of starch depos- 

 ited in the bark and in the fundamental tissue, which occupies 

 the greater part of the central- cylinder. Immediately inside 

 the epidermis some small groups of stereome are to be 

 observed, and this tissue appears again in about three or four 

 strata, forming a closed ring inside the bark, and surrounding 

 the central- cylinder. A thin- walled endodermis is very dis- 

 tinct, and the collateral mestome-bundles are arranged very 

 regularly in three alternating bands, with their hadrome-side 

 supported by thin-walled stereome; similar, but smaller, 

 mestome-bundles were, also, observed in the bark. Tannin- 

 reservoirs were observed to be quite numerous and of large 

 size in the bark. 



If we now compare this structure with that of a tuberous 

 internode, we notice the almost complete disappearance 

 of the stereome, and also that there is here only one 

 single band of collateral mestome-bundles, located a very 

 short distance from the epidermis. The fundamental tissue 

 occupies the greatest part of the internode and is filled 

 with starch. It appears from this, that the function of these 

 thickened internodes is for the storage of nutritive matters ; in 

 the Graminece, however, their function is different, according 

 to HackePs observations, who states that he was unable to find 

 any deposits of starch in their swollen internodes, although 

 these were examined at different seasons of the year. He, 

 therefore, concludes that they may represent a kind of water- 



