~ 1899] PODOPHYLLUM PELTATUM 431 
scattered very irregularly. The cylindrical petiole ofa young leaf, 
developed from the rhizome, has only four peripheral mestome 
bundles in the cortex, and one in the center of the pith. Corre- 
sponding with the stem above ground, the mestome bundles of 
the petioles are supported by sheaths of quite thick walled stere- 
ome, especially on the leptome side. 
Characteristic of the root is the strong thickening of the outer 
walls of the epidermis, even in roots of very young specimens. The 
cortex is solid, with no lacunae, and the innermost layer is differ- 
_ éntiated into a thin walled endodermis. Five groups of vessels 
alternate with a corresponding number of leptome groups, bor- 
| dering on the pericambium, and the innermost part of the 
central cylinder is occupied by a thin walled conjunctive tissue. 
In considering these anatomical peculiarities, especially the 
structure and arrangement of the mestome bundles, it cannot be 
i denied that Podophyllum possesses a very anomalous internal 
Structure. The morphological characteristics which have been 
discussed above, the manner of germinating, and the peculiar 
Tamification observable in the rhizome are seldom met with in 
_ dicotyledonous orders; and the creeping rhizome with its mono- 
Podial shoots reminds us very much more of the monoco- 
‘tyledons, 
Hence, when the “ mesophytes,” to which our plant is said 
LY belong, have been characterized as possessing ‘‘no very pro- 
ounced or interesting features in anatomical or morphological 
_ Tspects,” the statement does not seem applicable to /’ odophyllum 
_beltatum. Neither does it hold true if we examine the other 
herbs that constitute the vegetation in the deciduous forests of 
. North America. Many of the herbaceous species which as 
_ Seterally associated with Podophyllum show morphological 
- *Peculiarities that are very conspicuous and characteristic. It 
_ Would, indeed, be difficult to point out a vegetation in this coun- 
: ity that contains a larger number of herbs with as varied and 
Meresting morphological structure as our forest plants, lately 
Classified simply as “mesophytes.” Podaphyllum peltatum prefers 
© Wooded belts in this country, and its nearest associates, 
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