el i tenk errr) a bist 
® 
TRIANDRIA. DIGYNIA. 85 
Flora Atlantica. ‘To the present section of this genus ap- 
| pertains the #. hirsuta of Egypt, and the &. Coalora- 
chis of the isle of Tanna in the Pacific. The R. monan- 
dra of Spain, appears to be almost an Andropogon, from © 
\ the diagnosis. ‘ 
The genus Rotbollia, though not numerous in species, 
: appears to have been dispersed upon every known sea- 
. coast; they are found upon all the coasts of Europe, of 
Northern Africa, of America, of India, and of Australia, 
as well as upon the remotest shores of the latest disco- 
vered islands in the Pacific. 
116. TRIPSACUM., L. ms 
Masculine calix 2-valved, 2-flowered. Corolla 
*2-valved, membranaceous, imperforate at the 
base. Female calix 1-flowered, 2-valved, ex- 
terior valve indurated, resembling an involu- — 
crum of one leaf, with 2 small perforated sinu- 
Ses at its base. Corolla valves numerous, very 
thin and membranaceous. Styles 2, exserted. 
Seed large, ovate, arillate. Ae 
Nearly allied to many species of the preceding genus. ~ 
Flowers monoicous, disposed in spikes, which are ag on 
or aggregated, upper ones masculine, brought together 
by pairs, each 2-flowered; female calix 2-valved, the exte- 
rior valve indurated, firmly closing the scrobiculum, but 
perforated by 2 small sinuses at its base, and an emargi- _ 
’ nation, or bifid apex for the egress of the styles whichare 
plumose and exserted; valves of the corolla inyolate, mMem- 
branaceous, about 6, extremely thin, 4 of the ably 
rudiments of flowers which are constantly. 
want of space. Seed large, roundly ovate, 
somewhat gibbous. Perisperm large, corneot 
rinaceous; corculum laterally attached, naked. — : 
pay rium of the male flowers 2-leaved, truncate and emargi- 
nate. a 
: sa Species. 1. T. dactyloides. On the sea-coast, and also 
in the vast prairies of the western states. Z. Collins, _ 
Esq. informs me of its €xistence near the banks of the 
Schuylkill, 25 miles above Philadelphia 2. monostachyon. 
_A North American genus, PS ee get “ 2 
117. ZEGILOPS. L. 
Cali lateral, 2-valved, mostly 3-flowe 
. 
vg 
