9 
Anatomie. 
paper the author describes the structure of six representatives ot 
the three sections, the composition of the inflorescence, the struc¬ 
ture of the subterranean axis, the seedling, and finalty the anatomy 
of the vegetative organs: root, stem, and leaf. The seedling has an 
epigeic, filiform cotyledon, and the primary root grows and remains 
active during the first season; three leaves appear already, in the 
first year, and the3 r show the same structure as the ultimate, being 
ensiform. In this respect our genus differs from Iris , for according 
to Klebs the cotyledon of I. Pseudacorus is hypogeic. The subter¬ 
ranean stem is ver}^ short, the majority of the species being cespi- 
tose, but in 5 . Californicum there is a horizontally creeping rhizome 
with the internodes very distinct. The leaves are two-ranked, equi- 
tant, and the aerial stems strongly compressed, except in S. grandi¬ 
florum, in which leaves and stems are approximatety cylindrie. 
The material examined consisted in specimens from sand} r soil 
near Brookland, D.C. (S. angustifolium, and anceps)\ from gravelly 
soil along creeks on Long’s Peak, Colorado, at 9000 ft. ( 5 . mon - 
tanum)\ from low, sandy pine-barrens near Eustis, Florida {S. 
xerophyllum)', from dry hillsides in Oregon ( 5 . grandiflorum ); from 
swamps at Bodega, California ( 5 . Californicum ), and finally the 
roots were examined of the tuberous-rooted 5 . alatum from Lava- 
fields, at 8,500 foot in Mexico. But in spite of the fact, that these 
specimens thus originated from stations of very distinct nature 
and widely separated, the internal structure is ver} T uniform, and 
no character has been observed that might lead us to adopt the 
recent Classification of the species under three genera, instead of 
only one: Sisyrinchium. The root-structure, for instance, is ver} r 
uniform, and the onty deviation was observed in regard to the pe- 
ricambium, which in S. xerophyllum , and montanum sometimes 
consists of two layers, besides that it may be interrupted by the 
proto-hadrome-vessels. In the tuberous roots of vS. alatum , the cortex 
is very broad, filled with starch, and the cell walls very distinctly 
thickened; but otherwise the structure of epidermis, exodermis r 
endodermis, pericambium etc. is identical with that of the other 
species. With exception of 5 . grandiflorum the stem is ancipital, 
the wings varying somewhat in breadth, while the central portion 
is, always, cylindrie. No collenehyma was observed, but stereome, 
which forms a closed sheath, in the C3 T lindric portion, and occurs 
as isolated Strands, covering the leptome, in the wings. 
The mestome-bundles are arranged in two concentric bands in 
the cylindrie portion, but in a single plane in the wings. In S. 
grandiflorum the peripheral mestome-strands are imbedded in the 
cortex, while in the other species both bands are in contact with 
the stereomatic sheath. In regard to the foliar structure the follow- 
ing points may be mentioned. The proph}Tlon is membranaceous, 
almost destitute of Chlorophyll, and strongly compressed; it is fre- 
quently scabrous on the dorsal face, and contains more than two 
mestome-strands. In the green leaves the peculiar manner in which 
the blade, or better the dorsal face has become developed, naturally 
causes a more or less complete turning of the mestome-strands, 
thus we observe an almost regulär alternation of leptome, and ha- 
drome on each side of the blade. Otherwise the mestome Strands 
are collateral, partly surrounded by stereome, and are, thus, located 
in a single plane. In 5 . Californicum of the section Echthronema 
the leaves are not so compressed, and the mestome-strands are here 
arranged in a narrow, elliptical band with the hadrome turned in- 
