28 MISSOURI BOTANICAL GARDEN. 
World, and Dracaena, Cordyline, Astelia and Milligania, 
of the Old World, while the South American Herreria is 
removed to another tribe. 
Professor Engler,* who treats the Aloineae as pertaining 
to a group placed at a considerable distance from the 
Dracaenoideae, includes in the latter the Old World Dra- 
caeneae, of the genera Cohnia, Cordyline, Astelia, and 
Milligania, with perianth segments connate at base, and 
the New World groups Nolineae, of the genera Molina and 
Dasylirion, and Yucceae, of Yucca and Hesperaloe, with 
the segments distinct.t Hesperocallis is very properly 
removed to another group. 
The present paper deals only with this group Yucceae of 
Engler, and includes the principal conclusions reached in 
an intermittent herbarium, garden and field study extend- 
ing over the last sixteen years, in the course of which nearly 
all of the spontaneous species have been examined and 
photographed in their native homes and many of them in- 
troduced or reintroduced into cultivation in this country 
and Europe from definitely located sources. 
In its alliance, the group Yucceae is characterized by the 
possession of similar subequal withering-persistent petaloid 
perianth segments, a 3-celled ovary with more or less in- 
truded dorsal false septa, many ovules 2-ranked in each 
cell, a subterete elongated embryo obliquely placed across 
the seed, and germination with arched cotyledon.t 
* Natiirl. Pflanzenfamilien. II Teil. 5 Abteil. 19, 70. (1888). 
{ It is to be observed that, with most writers, Engler speaks of the 
segments as free or somewhat united at base, in his generic description 
of Yucca. —1. c. 70. 
t In all of the genera of this group, in germination the cotyledon as- 
sumes an arched form, with the seed remnant on or in the soil (from which 
it is ultimately raised in some cases), instead of directly carrying this 
up on its end as it commonly does in Liliaceae. — See The Garden. 83 
300. f. — Gard. Chron. n. s. 24: 216. — Lubbock, Contr. Knowl. of Seed- 
lings. 23 578, 613. — Copeland, Bot. Gaz. 813 419. f. 3. 
