470 SCIENCE PROGRESS. 



African forms still lingering as far eastward as Afghanistan, 

 notably the very distinct genus Fingerhuthia (Gramineae), 

 which Dr. Aitchison found in abundance (50) in the 

 Kuram valley. We regarded it as the same as the extra- 

 tropical South African F. africana, the only other species 

 of the genus; but Boissier (51) describes it as a new 

 species ; on exceedingly slender characters, it must be said. 

 This however, though an extreme example, is an isolated 

 one ; and although Schweinfurth (52) found the vegetation 

 of Western Yemen and Abyssinia almost identical, the. 

 affinities of the floras of South Arabia and Socotra are not 

 nearly so strong as might have been expected. This is 

 evident from a report on the botany (53) of Bent's Hadra- 

 maut expedition of 1894. 



Balfour's table on the ordinal composition of the phane- 

 rogamic flora of Socotra reveals some interesting facts. 

 Leguminosae stand first with twenty-five genera and fifty- 

 three species, including one endemic genus and sixteen 

 endemic species; Graminae second with twenty-eight genera 

 and fifty-one species, one endemic genus and five species ; 

 followed by Compositae with twenty-two endemic species ; 

 Acanthaceas with three endemic genera and twenty-one 

 endemic species, out of a total of twenty-seven ; Ascle- 

 piadese, two endemic genera and eight species ; and 

 Scrophularineae takes the sixth place with twelve genera 

 and thirteen species, including one endemic genus and four 

 endemic species. These six orders combined contribute 

 1 16 genera, 201 species, eight endemic genera, and seventy- 

 six endemic species. These figures speak for themselves, 

 but the large proportion of endemic species of Composite 

 and Acanthaceae is remarkable, though quite in harmony with 

 the discovery of an enormous number of new species of 

 this order by recent travellers in eastern tropical Africa. 

 Orchideae are rare in most islands, even in those of moderate 

 distance from continents ; due probably in some degree to 

 the absence of favourable conditions. HabenaiHa <ocotrana 

 is the only species hitherto discovered in Socotra, where it 

 is endemic, and probably rare, as Balfour's party met with 

 it in only one spot. It is described as being closely allied 



