314 The Botanical Gazette. [Augest, 
cation of the axis. We have here three forms of shoots: (i) 
‘‘vegetative - floral,” where the leaf-bearing axis is termin 
ated by the inflorescence; (II) ‘‘floral,” the leaves of which 
are sheathing and bladeless; and (III) ‘‘vegetative,” which 
bears leaves of normal shape, but where no inflorescence be- 
comes developed, at least not in the first year. 
The true ‘‘vegetative-floral” axis is the main stem itself 
the ‘‘vegetative,” on the contrary, representing a secondary 
axis. The‘‘floral’shoot is also always secondary, and illustrates 
a biaxial ramification, such as is known from, for instance, 
few species of Carex”, and others of various families. 1 
main-shoot is in these purely vegetative and develops contin: — 
uously only leaves,from the axils of which the flowering stems — 
become developed. . 
Most of the species of Xyrzs show the development of a 
“‘vegetative-floral” main-axis, while in others the main axs6 — 
merely ‘‘vegetative.” Xyris savannensis, however, shows all | 
three forms of shoots upon the same individual. The ram> 
fication becomes still more complicated, when two oF even 
three shoots develop in the axil of each leaf; such shoots sak 
either all ‘floral,” or ‘‘floral” and ‘‘vegetative-floral. 
The roots occur in the two forms ‘‘typical” and agg 
n structure. 4% — 
teresting is the fact, already discovered by Van 
that the pericambium is interrupted b 
Xyris, have the central part composed of gees” very 4 
that the pericambium and the endodermis con® f 
thick-walled cells. ground thi 
The stem is mostly differentiated into an pages 
zome with sympodial ramification, and pies 
- flower-bearing scape. Xyris witseniowdes fo 
tion by having a distinct stem above-ground, ( 
*WypLeR: Ueber die Axenzahl der Gewachse. 
also: CattmE: Ueber zweigliedrige Sprossfo we 
Carex. Berichte d. deutsch. bot. Gesells. v. heft ee des radicelles 4288 a 
*Van Tieghem: Structure dela racine et disposition afeq por | 
Centrolepidées, Eriocaulées, Joncées, Mayacées ¢t 
