174 BOTANICAL GAZETTE [SEPTEMBER 4 
the various serial sections of seedlings may be due to some of them 
belonging to T. erectum rather than to T. grandiflorum, since the 
seedlings of the two species are hard to distinguish in the field, and I 
have been unsuccessful in attempts to grow them from seed. In 
many instances a leaf trace arises from one side rather than from the 
__ base of the gap, as has been observed in many ferns, or the trace may 
run vertically for some distance before turning out from the stelar 
ring. This condition is shown by the trace marked #¢, in fig. 22; 1, 
and #, are the lateral traces of the same leaf; the last has not quite 
broken away from the stele. 
TRILLIUM SESSILE and T. RECURVATUM greatly resemble T. granti- 
florum in the seedling stage, but differ from the last species in having 
wider gaps and showing concentric bundles in a younger part of the 
stem. 
ASPARAGUS OFFICINALIS, A. VERTICILLATUS, A. SPRENGERI, A. 
VERTICILLATUS, A. BROUSSONETII, and A. MEDEOLOIDES do not appear 
to throw any light on the problems under consideration on account of 
the complications attending the formation of lateral buds. 
Ruscus acuLratus has a seedling much resembling those found 
in the genus Asparagus. In the seedlings available the stele had 
already assumed its mature condition. : 
Dracaenoideae.—Yucca FILAMENTOSA.—The hypocotyledonary 
stele consists of a hollow vascular tube from which about one-third 
of the vascular tissue turns outward to the cotyledon, leaving 4 U- 
shaped stele whose pith is in free communication with the cores 
No phloeoterma was observed. Almost immediately strands tum 
from the U into the pith, and before the cotyledonary gap 1s closed 
these medullary strands are quite numerous. These become tract 
of higher leaves, so that the stele in this plant quickly attains the char 
acteristic monocotyledonous condition. Nearly all the vascular 
strands are collateral. ee 
Yucca ANGustIroLIA and Y. BAccATA resemble Y. jilamentosa® 
the young state; in the first-named species the medullary bundles at 
somewhat later in arising than in the two other species. - 
Dracaena Draco, D. RUBRA, D. Verrcut, and CorDYLINE ot ft 
TRALIs differ in no essential respect from Yucca as regards the develop 
ment of the stele. = 
