108 
sus none. Farther into the cortex the latter regularly has 
no bastcells or vascular bundles, but exceptionally there 
exist 1—2 small strands ( tedency to become cortical mecha- 
nic cells) and really f. puyensis exhibits 2 small bundles of 
4—5 cells within the circle of cortical vascular bundles, that 
occur by this form just as in P. gramineus. For the rest 
the stem-structure wholly agree to P. gramineus: endoder- 
mis of u-cells etc. 
The habit of the plant closely corresponds with that 
of P. gramineus. Lower branches bearing shorter branch- 
lets of higher degree, making their appearance very bushy. 
Stem prolongates itself by branches of F to 2 d rank, each 
developing 2—3 internodes, by what plenty of floating lea- 
ves (about 10) exist; the blades 13-nerved, oval with an ob- 
tuse cuspis, ^ ^ mm, petioles ca. 80 mm, their stipules 
brown with low ribs, 35—40 mm long. Under the primary 
floral leaves the stem-leaves and their stipules already the 
10 th of july are destroyed, which conspicuously signifies 
relationship to P. nodosus. Leaves of the branchlets of the 
last rank extremely small, only 7 y " mm. Peduncle ca. 
50—80 mm of the same thickness as the internode beneath. 
3 
spikes 40 mm (in fruit). Fruit ^ mm with a short subapical 
beak, commonly failing. 
»Gallia: Vienne in stagno dicto de la Puye> 10 julio 
1900. E. Simon.» 
2. Forms belonging to the 2 d series (nodosifolia) occur 
im New England, U. S. A., whereof specimens lie in the 
university-herbarium at Uppsala and what will be described 
in another work. 
