T. Holm — Studies in the Cyperacece. 325 



readily understood, when we compare the inflorescence 

 with that of Tuckermann's section Vigneastra, for 

 instance C. cladostachya Wahlenbg.^ 



The accompanying figures (2 and 3) show the ramifica- 

 tion. In C. cladostachya {fig. 3) only a small part of the 

 culm has been shown (St.) ; it bears a green leaf (L.), 

 which subtends a rhachis (R.) bearing four androgynous 

 spikes of which only the three have been shown; the 

 rhacheola is terminated by an androgynous spike (S.). 

 The racheola bears three long, leaf -like bracts 1^ and P 

 (the third one, the uppermost, is not marked). In the 

 axils of these bracts are spikes, one in each, and they bear 

 a distinct ochrea (P*). In C. cladostachya these ochreae 

 (P*) are exposed to the light; they are of a dark brown 

 color, and often hairy, while the basal ochrea (P) is 

 membranaceous, hyaline, and partly hidden by the base 

 of the leaf (L.). If we now compare the schematic 

 drawing of C. ternaria {fig. 2) which represents a whorl 

 of three spikes, we notice the striking accordance with the 

 composition of the spikes in C. cladostachya. 



We notice the small part of the culm (St.), bearing a 

 green leaf (L.), which subtends a rhachilla (R.)? bearing 

 two lateral, androgynous spikes and a terminal (S.). At 

 the base of the rhachilla is an ochrea (P), turning its 

 back towards the mother-axis (St.). The two lateral 

 spikes are also provided with ochreae (P*) but these are 

 membranaceous, hyaline. Two bracts (P and 1^) are 

 indicated with dotted lines, since they are not developed. 

 By comparing this figure with C. cladostachya, the only 

 difference depends on the very long rhachilla, the very 

 short, lateral axes and the development of the bracts 

 (P-P) in C. cladostachya, while in C. ternaria the rha- 

 chilla is very short, the bracts are suppressed, and the 

 lateral axes are long. To render the position more dis- 

 tinct we have drawn the rhacheola in the latter species 

 much longer than it is, and the uppermost lateral axis 

 has been drawn much shorter than it is, in order to save 

 space. As a matter of fact the length of the basal por- 

 tion of the rhacheola in C. ternaria, between P and the 

 uppermost P*, is only one min. ; thus the ochreae (P and 

 P*) are situated almost at the same height. Wliile these 



^ Compare this Journal, vol. 10, p. 36, 1900. 



Am. Jour. Sci.— Fifth Series, Vol. II, No. 12.— December, 1921. 

 38 



