296 BRYOPHYTA OF S. RHODESIA. 



The relationship of the Zimbabwe and eastern mosses is 

 almost entirely with species found further south; the relationship 

 of those found at the Victoria Falls is only to a very small extent 

 with the mid-African flora, probably accounted for by the long 

 distance of arid country by which that site is separated from other 

 suitable localities northward. Even trees seem to have travelled 

 along the Zambesi from mid and western Africa more easily than 

 Bryophyta. 



The endemic species are mostly from the Victoria Falls. 



Aongstroemia gyvinovdtrioid.es Dixon is a most interesting 

 pioneer on bare flat rocks, abundant at Zimbabwe, present else- 

 where, and closely related to a Natal Drakensberg alpine species, 

 both being closely related to a far South American mountain 

 species, and very distinct as a group from all other mosses. 



The western part of Rhodesia will probably not yield many 

 more mosses until more closely settled, but the eastern part, 

 particularly Umtali and Melsetter, is furnished with forest areas 

 where forest mosses may be expected to exist in abundance, but 

 which bryological collectors have still hardly touched. These 

 parts of the escarpment, together with its eastern face in Portu- 

 guese East Africa, for a bryological terra incognita from which 

 a rich harvest may be expected when their close investigation is 

 undertaken. Below these the Portuguese flats are arid and almost 

 without mosses; even where trees abound along the river banks 

 the subsoil is moist, but the atmosphere is very arid. 



II.— HEPATIC AE. 



T. R. Sim, D.Sc, F.L.S. 



fficcia fluitans, Linn. "Spec. Plant." p. 1606. 



This belongs to section Ricciella, sometimes treated as a 

 distinct genus. 



Zimbabwe, 3,000 feet, Sim 9065; Khami Stream, Sim, 

 9067; Victoria Falls Rain Forest, Sim, 9066; Matopos, Miss 

 Gibbs, 318. Usually found floating in water or set in mud. 



General distribution: Frequent in all sub-tropical countries. 



Riccia albomarginata , Bisch. "Syn. Hep." 604. 



Matopos, 5,000 feet; Sim, 9068; Stream at Bulawayo, 5,000 

 feet, Sim, 9069; Zimbabwe, 3,000 feet, Sim, 9070, 9071, 9072; 

 Rhodes' Grave, Matopos, 5,000 feet, Sim, 9073. 



General distribution : Tropical and sub-trcpical South Africa. 



Targionia hyophylla, Linn. "Spec. Plant," p. 1,604. 



Matopos, near Hotel: 5,000 feet, Sim, 9080. 



General distribution: Africa, Southern Europe, South 

 America and Australia. 



Pleigiochasma rupestre, St. "Spec. Plant." p. 783. 



Matopos, Eyles, 937 and 1181; Zimbabwe, Sim, 9081. 

 General distribution: Mediterranean and Africa. 



