442 T. Holm — Studies in the Cyperacece. 



stenophylla (fig. 9) are the double rows of diverging, pointed 

 hairs along the margins and the ribs on the lower surface of 

 the blade. 



Although F. complanata is not a native of this country, we 

 have examined some specimens, as stated above, from Uruguay, 

 which were originally labeled F.autumnalis, to which it shows 

 a very pronounced habitual resemblance. The position of the 

 leaves are exactly the same, distichous with the blade held 

 edgewise ; besides the inflorescence is very rich-flowered. How- 

 ever, while we examined the anatomy we became aware of the 

 fact, that in this respect onr plant showed a leaf-structure dif- 

 ferent from that of F. autumnalis, but almost exactly like 

 that of F. thermalis. In order to secure correct identification 

 of this South American species, we sent specimens to Mr. C. 

 B. Clarke at Kew, who kindly replied that the plant was Link's 

 F. complanata var. Kraussiana. If Dr. Boeckeler had known 

 of the structural divergencies between this and F. autumnalis, 



Fig. 1 Fig. 8. Fig. 9. 



Leaves of F. ciliatifolia, F. Warei and F stenophylla; transverse sections, x 75. 



he would hardly have considered them as but one species, 

 even if the outer likeness is very striking. 



If we now compare the leaves, of which we have drawn 

 some transverse sections from the middle part of the blade, it 

 is readily seen that the outline and the structure of the upper 

 epidermis presents certain features for distinguishing the 

 species. Nevertheless these leaves demonstrate several 'inter- 

 gradations, thus the various forms may be easily deducted 

 from one another. The epidermis of the upper surface is 

 either developed as one single layer of large, bulliform cells, 

 or as several strata, that cover- the mesophyll. None of these 

 strata are, however, differentiated in such a way as to have the 

 function of opening or closing the leaf, the so-called " Gelenk- 

 cellen " of the Germans, common to Cyperacece and Graminece. 



In passing, to describe the minor details of the leaf -structure, 

 we observed the cuticle to be very thin and smooth in F 

 autumnalis, F. laxa and F complanata, less so in F. spadicea ; 

 in the remaining species the cuticle is very thick, but smooth, 

 not granular. The epidermis of the lower surface is almost 



