66 MISSOURI BOTANICAL GARDEN. 
distinctions, however, perhaps it is well to make use of the 
substantive names used by Mr. Baker for these divisions, — 
ManrFrepa (Salisb.), Lirrana (Tagl.), EuaGave (Baker), 
and also to use the terms employed by him to designate 
the groups formed on leaf characters, though so far as they 
apply to our United States species, I cannot follow him 
strictly in their application. 
It must constantly be borne in mind that the variability 
of species within the genus is so great that any attempt 
to draw precise lines in classification results in failure. 
A. Lechuguilla has been found with flowers in clusters* of 
from three to ten instead of in pairs. Both with reference 
to leaf and floral characters, A. Utahensis might almost 
as well be grouped with Euagave as with Littaea. Some 
six or eight plants of A. brunnea Watson, of the Manfreda 
section, bloomed at the Garden last June. Most of these 
plants bore single flowers in the axils of their bracts. One 
plant of a vigorous growth, showed at two points a second 
flower in the axil of the lateral bractlet. One of these was 
sessile and the other pedicellate, as shown in plate 63, 
figs. 8, 9. Dr. Engelmann notes a case f in which a plant 
of A. Virginica produced secondary flowers year after 
year. In his plant a third flower sometimes appeared. In 
leaf characters many instances could be cited of departure 
from the normal form. A. parviflora of the group Filiferae 
has been considered unique in bearing teeth as well as fila- 
ments, but the Garden has recently received a specimen of 
A. Schottii from Professor Toumey which shows the same 
peculiarity. 
I subjoin the general schemes of classification adopted 
by Terraciano and Baker. 
* Dr. Engelmann, Gard. Chron. Jan., 1888, 48.— A. heteracantha, 
Engelm. 
+ Collected Writings, 303. 
