a BOTANICAL GAZETTE [SEPTEuner 
pursue the course ordinarily seen in a monocotyledonous stem. ion 
no part of the stem is an endodermis well developed. ae ot 
Colocasioideae.—ALocasIA opORATA.—Above the point of exit 
of the cotyledonary traces the stele is represented only by a scanty 
vascular mass of flattened form, its side being turned toward the 
cotyledon. Further upward this mass splits into several strands, 
and a ring-shaped row of bundles is completed by the appearance de 
novo of several delicate strands between those already present and 
the cotyledon. The flattened vascular mass referred to seems to 
represent the same condition as that shown for Peltandra in fig. 11, 
namely, there is an unusually wide cotyledonary gap, which is not 
closed in the ordinary way owing to the tendency throughout the plant 
for the vascular strands to lie widely separated. Ina slightly higher 
region of the stem several bundles come to lie in the medulla and some 
of the bundles assume the amphivasal shape. No endodermis was 
found in any part of the stem. 
CALADIUM BULBOSUM.—Departure of the cotyledonary trace 
causes no break in the narrow stele of the seedling; the stele soon 
becomes complicated by medullary strands which anastomose with’ 
one another. In many sections, however, it may be seen that the cH: 
cortex communicates freely with the medulla above the point of exit 
of a leaf trace. No endodermis has been demonstrated. . . 
Aroideae. ARUM ITALICUM.—The five traces which pass into the | 
sheathing base of the cotyledon arise from a complex vascular mass; 
and the succeeding traces run for a short distance in the medulla. 
The peculiar habits of sprouting described for another member of the _ 
genus by RimBacH (10) and Scorr and SarGAnT (13) have probably 
had the effect of modifying the vascular system; and no part of ne 
plant suggests a primitive condition, but on the contrary 4 highly 
specialized one. ae 
ARISAEMA TRIPHYLLUM.—The method of sprouting is essentially — a 
like that of Arum. The five cotyledonary traces rise from a V ae 
mass whose elements anastomose in a complex manner. Above ee . 
region the bundles pursue a more nearly vertical course, but areas mo 
arranged in a definite central cylinder surrounded by endodermis ts 
In older seedlings the bundles form an extensive network in rs = 
central region of the corm. It is probable that the phylogenetic 
