BY L. RODWAY. 05 



on grr.ssy lulls, but easily overlooked. Apparent onlv in 

 Avinter and spring. 



Riccia cra.-<m, St. — Fronds 1-2 cm. long, 3 mm. wide, 

 simple or forked, apex obcordate, upper surface concave, 

 with a shallow acute median groove, wings becoming con- 

 vex with age; margin acute undulate, often tinged with 

 purple; chlorophyllous stratum rather dense, with narrow 

 air spaces, cells about 40 ^ diameter. Spores light brown, 

 70 /A. diameter, convex surface with shallow reticulations, 

 .about 10 areolae, flat faces nodulose. Ventral surface con- 

 vex. Three times as broad as deep. 

 Lindisfame, Central Australia. 



Riccia weymfjuthiana, St. — In general appearance and 

 structure not differing from the last, only spores rather 

 larger, 80-90 fx., and the air spaces large and bursting 

 through the upper surface. Doubtfully distinct. 



Lindisfame, Mt. Abrupt. 



ElCCIOCAEPL'S CORDA. 



Obcordate seldom forming rosettes, upper surface with 

 a median furrow, and furnished with pores; chlorophyll- 

 layer not well defined, nearly the entire thickness occupied 

 by air chambers; ventral surface, with numerous long, 

 dentate, violet-coloured scales. Antheridia collected in the 

 median furrow. 



Ricciocarpus natans (L.), Corrln. — Obcordate about 1 

 cm. long, flat, scales about 5 mm. long. 



Floating on a lagoon, George Town; Cosmopolitan. 



^^vl ARCHANTI A C E AE . 



Fronds flat, procumbent, dichotomcusly dividing, dor- 

 sal surface with well developed pores, opening into simple 

 or compound air spaces; ventral surface with two or more 

 lines of scales ; reproductive organs grouped, usually on 

 special branches. The branches bearing fertilised ova, as- 

 suming a specialised character, usually in the fomi of an 

 erect umbrella-shaped body (carpocephalum). Well de- 

 veloped elat.ors always present. 



Pores simple. 



Targtonia. — Sporophyte enclosed in a pair of large 

 bracts, partly concealed beneath the edge of the frond. 



Reboulia. — Sporophytes on a persistent carpocepha- 

 lum. Not bearing gemmae. 



LuNUEARiA — Sporophytes on a perishing cari30cepha- 

 lum. Gemmae always present in a crescent-shaped recep- 

 tacle. 



