CXLVI. MARSILEACER. 683 
1. MARSILEA, Linn. 
Rhizome creeping and rooting at the nodes. Barren fronds with a 
long petiole or stipes, the lamina divided into 4 digitate leaflets, with 
numerous forked veins radiating from their base. Involucres sessile or 
stipitate, their stipes often but not always combined at the base with 
those of the barren fronds as in Ophioglossex. Sori linear, on trans- 
verse veins proceeding from the upper side or midrib of the involucre, 
the indusia often more or less combined, dividing the involuere into 2 
series of transverse cells. ^ Each sorus consisting of few macro- 
sporangia, each one surrounded by several mierosporangia. 
ü e ge i nge in the northern hemisphere and one of the Austra- 
an species does not appear to be distinct from the common northern one. The 
others are proba ly endemic. 
Lin. . . o. L M. quadrifolia. 
Leaflets narrow-oblong. Involucres hirsute, sessile or nearly 
"os Ec ee a cia ge ea E I uo 
Leaflets obovate usually hirsute. Involucres hirsute, sessile 
OF AMI. Seton e fo ees seg oes TOME MEIN 
xpi obovate, often crenate; silky-villous underneath. 
volucres on stipes of 1 to nearly 2 in. 4. M. Drummondii, 
: no difference between these and European specimens except that the 
stipes of the involucres are usually but not always rather longer and almost but 
not quite free from that of the barren frond. 
N.S. Wales. Port Jackson, R, Brown. 
2. M. angustifolia, R. Br. Prod. 167.—Leaflets narrow-oblong, 
very obtuse truncate or slightly toothed at the end, the stipes slender, 
filiform, 2 to 3 in. long in Brown's specimens, above 1 ft. in F. 
Mueller’s, glabrous or nearly so. Involucres hirsute and nearly sessile 
as in M. hirsuta, but in the few specimens seen solitary at the nodes. 
_N. Australia. Islands of the Gulf of Carpentaria, R. Brown ; Victoria River, 
F. Mueller. 
. 3. M. hirsuta, R. Br. Prod. 167.— Young ends of the rbizome 
densely rusty-villous. Leaflets obovate or broadly cuneate, sparingly 
or densely hirsute underneath, the stipes usually long and slender. 
Involucres small, usually clustered, sessile at the base of the barren 
fronds or on a stipes shorter than the involuere.—A Br. in Berl. 
Monatsber. 1870, 732. 
N. Australia. Islands of the Gulf of Carpentaria, R. Brown ; Victoria River, 
F, Mueller, 
