GENUS PASSERINA. 231 



spots on the Cape Flats, usually along with Dovea teetotum, 

 appears not to have been collected before. 



Additional evidence of the new classification is afforded by 

 the consistency of the distribution of those widely spread, in 

 contrast with the confused distribution recorded in the "Flora 

 Capensis." 



Until it has been possible to examine the material in the 

 European Herbaria names cannot be assigned with certainty, 

 though some are here employed tentatively, in conformity with 

 their current application. The widely distributed species are 

 five in number, each with a well-defined habitat and range. 

 Passerine fill for mis is the common species of the maquis 

 of the South-West Cape; P. rigida is characteristic of exposed 

 sand dunes near the sea from Muizenberg to Durban and beyond; 

 P. ericoides is the species of high altitudes, extending on the 

 Drakensberg and associated high mountain ranges from the 

 Eastern Province to Umtali ; ihe species called by Natal botanists 

 P. filiformis but distinct from the south-west species is found in 

 the outer fringes of the scrub and forest in Natal and in the 

 neighbouring regions to the south, and also at the north-west part 

 ■of the Cape Peninsula, especially on the mountain buttresses; 

 finally a species, which is probably Meisner's P. rigida var. 

 truncata, extends from Tulbagh northward along the western 

 ranges, and into Little Namaqualand in and around the ares^ 

 characterised by a flora of the south-western type. 



The remaining forms have a more restricted distribution; some 

 are very local or rare. P. falcifolia is apparently confined to the 

 forest region of the Outeniqua and Zitzikamma Mountains, where 

 in the forest fringes it reaches nearly twenty feet in height. In 

 the Cape Peninsula five forms occur. Each of these has its charac- 

 teristic habitat. P. filiformis is found on well-drained sandy or 

 gravelly soil on the Cape Flats and the mountain slopes. The 

 form which has been confused with it is apparently confined to the 

 north-west corner, on the mountain buttresses, and also on the 

 western and north-western slopes on granitic soils of closer texture. 

 P. rigida is confined to the exposed sand dunes east of Muizenberg, 

 where it grows beside Ghymococca empetroides. A fourth species 

 is found on deep drift and farther from the sea; while a 

 fifth, not previously collected, is characteristic of brack marshes 

 and vlei margins on the Cape Flats. 



So far the da*a suggest forcibly that habitat is a factor of 

 prime importance in the distribution of the species. Further 

 research is required to determine what light the study of the genus 

 can throw on general problems of geographical distribution. A 

 peculiar anatomical feature of the leaves, an account of which 

 in P. filiformis is in course of publication,* is of significance here, 

 namely, the "wandering" of fibres laterally from the bundles 

 between the outer epidermis and the palisade tissue in certain 

 species. The presence of this feature in P. rigida indicates a close 

 relationship between this species and P. filiformis. 



* Since published in "Annals of Botany." XXXV., 1921. p. 585. 



