602 BRITTON: VEGETATION OF THE 
walled cell tissue containing the phloem patches. Endodermis 
formed of large thick-walled cells, reddish brown in color and 
strongly pitted and lamellated. Cortex composed of large irregu- 
lar thin-walled cells. All cells of the root are colorless. 
Diameter of root, .25 mm. 
s¢ «© central cylinder, .II mm, 
«¢  « central vessel, 33 
CarREX PENNsYLVANICA.— A section of the root shows six 
large vessels in central portion and just outside of the region 
occupied by the vessels occur the phloem patches. Endodermis 
composed of deep narrow cells with inner walls very much thick- 
ened, with pits and lamellae. Cells of endodermis and of central 
portion contain starch. Outside of endodermis are several layers 
of thick-walled, apparently empty, brown sclerenchyma-cells, 
only those of the first layer having a regular form. Some of these 
layers are separated or pulled off in places, forming large lacunes. 
Outside of this tissue are three layers of thin-walled parenchyma- 
cells. In some cases the tissue around the lacunes has separated, 
and the entire gap has been filled in by parenchymatous tissue. 
Diameter of root, .65 mm. 
‘« — * central portion, .35 mm. 
‘«  ** largest vessels, Re a 
Rhizome : central portion is composed of circular cells with 
rather thin pitted walls and devoid of large vessels. The bundles 
are arranged iia circle and the vessels are no larger than the 
cells in the central portion. _Endodermis apparent but not distinct 
as in the root : cells resemble others except that they have thicker 
walls and have a more regular arrangement. Cortex is made up 
of parenchyma-cells and separates from the central cylinder. 
There are three distinct vascular bundles in the cortex, probably 
belonging to leaf-scales or to branches. Some of the cells of the 
central portion contain starch. 
Diameter of rhizome, -95 mm. 
‘¢ —* central portion, -71 mm. 
oe wepsels, 20 4 
; ; le 
SALOMONIA BIFLORA (Polygonatum biflorum). — Root: bund 
contains from six to eight good-sized vessels with xylem arrans 
