34:8 T. Holm — Studies upon the Cyperaceoe. 



Aet. XL. — Studies upon the Cyperacece : by Theo. Holm. 

 (With Plate IX.) 



I. On the monopodial ramification in certain North-American 

 species of Carex. 



Two kinds of ramification are known to be represented in 

 the genus Carex: the sympodial and the monopodial. The 

 first of these is the most common, and species which exhibit 

 this ramification show only the development of one single axis, 

 which in its first year of growth merely develops leaves, until 

 it finally, two or three years later, passes over into a flower- 

 bearing stem. In this case the leaves and the flower-bearing 

 stem are both developed from the same bud. But in the 

 other kind of ramification, the monopodial, two special forms 

 of buds develop, the main one of which continues to develop 

 leaves, while the floral buds are constantly lateral. In 

 this case there are two different axes, and species which pos- 

 sess such kind of ramification are, therefore, biaxial. 



These two forms of ramification are easily recognized in our 

 species of Carex. The sympodial shows us a central flower- 

 bearing stem, the base of which is surrounded by more or less 

 faded leaves from the previous year, w T hile the monopodial 

 shows a central leafy shoot with a number of laterally devel- 

 oped flower-bearing stems. The terminal shoot, when purely 

 vegetative, can continue to grow for several years, and when it 

 finally dies off,* one or more vegetative buds develop from the 

 axils of its leaves, which grow out and repeat the same kind 

 of ramification. It is now interesting to note, that the mono- 

 podial ramification is only known as very rare in the genus 

 Carex. 



The German botanist Wydler deserves the credit for being 

 the first one to observe it in Carex, and he described it as 

 characteristic of two European species : C. digitata L. and C. 

 ornithopoda Willd.* Some years later Alexander Braun 

 attributed the same form of ramification to Carex pilosa Scop., 

 C. pendula Huds. and C. strigosa Huds.f It is difficult to 

 know, however, whether this statement of Braun is really cor- 

 rect. Doell has, at least, contradicted him so far as concerns 

 C. strigosa and C. pilosa,% and he states that by examining a 

 large number of specimens of C. strigosa, the flower-bearing 

 stems were constantly found to be central, and that he was 

 unable to detect any central vegetative shoot in C. pilosa. 



*Ueber die Achsenzahl der Gewachse, Bot. Ztg., 1844. 



\ Das Individuum der Pflanze in seinem Verhaltniss zur Species, Abhdlg. d. 

 k. Acad. d. Wissenseh, Berlin, 1853, p. 90. 

 % Flora von Baden, Carlsruhe, 1857. 



