1893.] The Philosophy of Flower Seasons. 773 
the summer, flower the Typhaces, which, as generalized-aber- 
rant Spadiciflorz, represent a rather more advanced degree of 
specialization than most Araces. Also in mid-summer come 
the remarkable little Lemnacew, usually considered a highly 
specialized-aberrant offshoot from Aracez, though the connection 
is doubtful. 
Among Liliiflore the three apocarpal orders, Alismacez, 
Juncaginacec, and Naiadaces, form a remarkably aberrant 
group, of few species, but wide-spread, particularly Sagittaria 
and Alisma. All come in late summer, and some among the 
exceptional non-glumaceous Monocotyls of autumn.  Potamo- 
geton, in Naiadaces, numbers a good many species, and comes 
late; but note that the genus is one of the most peculiarly 
specialized. 
All the Spadiciflorse and Apocarpal Liliiflore are scarce a 
tenth of the remaining Monocotyls, the Synearpal Liliiflore. 
This division naturally subdivides into the Hypogynæ and 
Epigynæ, somewhat parallel and closely inter-related. In the 
light of our present knowledge of the morphology of the 
hypogynous and epigynous flower there can be no doubt that 
the Epigynæ here represent the higher order of development, 
although many Hypogynæ may rise to a more than equivalent 
degree of specialization, —precisely as the genus Felis is con- 
sidered to represent a lower order of development but a higher 
degree of specialization than the anthropoid apes. 
In the non-glumaceous Hypogynæ most prominent is the 
order — P in which are, pre-eminently, typical and normal 
| Among the normal, particularly the more generalized, 
the fi first bloom in late April,—notably, for instance, Erythro- 
nium, about the earliest of Monocotyls. Scarcely later come 
Trillium, Uvularia, Smilacina, Polygonatum, Maianthemum, 
and others. Other genera extend through May and early 
June, and a few, finally, belong to mid-summer. Certain of 
these last, as Allium and Smilax, are, though normal, 
markedly more specialized than the principal spring-flowering 
genera. But the mid-summer genus Lilium claims peculiar 
prominence as an ideally “typical” genus in all the term 
implies. Lilium philadelphicum, L. catesbei, L. canadense, 
