CLV. MARSILEACE^. 1929 



1. MARSILEA, Linn. 

 (After Count L. F. Marsigli.) 

 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 

 OphioglossesB. Sori linear,'on transverse veins proceeding from the upper side or 

 midrib of the involucre, the indusia often more or less combined, dividing the 

 involucre into 2 series of transverse cells. Each sorus consisting of few macro- 

 gporangia, each one surrounded by several microsporangia. 



The genua has a wide range in tlie northern hemisphere and one of the Australian species 

 does not appear to be distinct from the common northern one. The others are probably 

 endemic. 



Whole plant glabrous. Leaflets obovate. Involucres on stipes not exceed- 

 ing Jio. and often very short 1. M. Brownii. 



Leaflets narrow-oblong. Involucres hirsute, sessile or nearly to . . . . 2. M. anguiti/olia. 



Leaflets obovate usually hirsute. Involucres hirsute, sessile or nearly so 3. M. hiisuta. 



Leaflets obovate, often crenate ; silky-villous underneath. Involucres on 

 stipes of I to nearly 2in i. M. Drummondii. 



1. TULm Brownii (after Dr. Robert Brown), A. Br. in Berl. Monat. 1863, 

 418 ; Baker's Fern Allies. Whole plant quite glabrous. Leaflets on a long 

 stipes, deltoid, ^ to IJin. long and broad ; outer edge rounded, quite entire. 

 Involucres obliquely ovoid or almost globular, 2 to 3 lines long, mostly in clusters 

 of 2, 3 or rarely 4, the stipes or peduncles not exceeding ^in. and often shorter, 

 more or less united at the base and very shortly so with the base of the 

 stipes of the barren frond. Sori about 15. — M. quadrifolia, Linn., Benth. Fl. 

 Austr. vii. 683. 



Hab.: Still waters of southern localities. 



2. JUL. augustifolia (narrow-leaved), R. Br. Prod. 167 ; Benth. Fl. Austr. 

 vii. 688. Leaflets narrow-oblong, very obtuse truncate or slightly toothed at the 

 end, the stipes slender, filiform, 2 to 3in. long in Brown's specimens, glabrous or 

 nearly so. Involucres hirsute and nearly sessile as in M. hirsuta, but in the few 

 specimens seen solitary at the nodes. Sori about 20. 



Hab.: Islands of the Gulf of Carpentaria, B. Brown ; Aramac, G. W. de Burgh Birch. 



3. M. hirsuta (hairy), R. Br. Prod. 167 ; Benth. Fl. Austr. vii. 683. Young 

 ends of the rhizome 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 fease of the barren fronds or on 

 a stipes shorter than the involucre. Sori about 15. — A. Br. in Berl. Monatsber. 

 1870, 732. 



Hab.: Islands of the Gulf of Carpentaria, R. Brown; Broadsouud, R. Brown; Brisbane 

 Biver, Moreton Bay, F. v. Mueller. 



Baker in Fern Allies describes this as a wide trailing terrestrial form, with leaves and fruits 

 in dense tufts at the distant nodes, and small silky leaflets of firm texture. 



4. M. Drummondii (after James Drummond), A. Br. in Linnaa, xxv. 721. 

 Baker's Fern Allies. Nardoo. Large sub-terrestrial or aquatic. Stipes often 

 Bin. long or more; leaflets deltoid, usually silky, 6 to 9 lines long; outer edge 

 rounded, entire or more frequently crenate. Peduncles sometimes exceeding 2in., 

 rigid, erect, adnate to the upper part of the base of the involucre. Involucres 

 oblique-oblong, not bordered, with the dorsal suture nearly straight, 3 to 4 lines 

 long, obliquely ascending, cuspidate, with a pair of smaller teeth at the upper 



