INTRODUCTORY CHAPTER. 



lxvii 



Thirty-one Socotran species come into the category of Asian species which do 

 not reach Africa, ten of them being annuals. The greater number of these are 

 found in the adjacent Arabian continent, but there are several which are not 

 reported from any portion of the south-west corner of Asia, and their occurrence 

 has therefore additional interest. Some of the species of sporadic area may be 

 accounted for in Socotra by supposing they are of comparatively recent introduc- 

 tion. Thus Crotalaria retusa, Psoralea corylifolia, Spermacoce hispida, Leucas 

 lanata are, I think, certainly of this character. But the occurrence of Hypericum 

 mysorense, Indigo/era Gerardiana, and Cylista scariosa cannot be explained in 

 this way. In the subjoined table the Asian species are enumerated, and their 

 geographical area outside Socotra is mentioned. 



List of thirty-one species of the phanerogamic flora of Socotra which 



are Asian but not African. 



Species. 



Viola cinerea, 

 Polygala chinensis, 

 Hypericum mysorense, . 

 Grewia orbiculata, 

 Acridocarpus orientalis, 



Geranium mascatense, 

 Balsamodendron Mukul, 

 Crotalaria retusa, . 

 Psoralea corylifolia, 

 Indigofera intrieata, 



,, Gerardiana, . 



Cylista scariosa, 

 Ammannia multiflora, . 

 Spermacoce hispida, 

 Statice cylindrifolia, 

 Vogelia indica, 



Cuscuta chinensis, 

 Solanum gracilipes, 

 Schweinfurthia pedicellata, 



Cistanche tubulosa, 

 Orthosiphon tenuiflorus, 



,, pallidus, 



Leucas lanata, 

 Psilostaehys sericea, 

 A triplex Stoeksii, . 

 Fliiggea Leucopyrus, 

 Pouzolzia aurieulata, 

 Lagarosiphon Roxburghii, 

 Cyanotis cristata, . 

 Pappophorum elegans, . 

 Eragrostis orientalis, 



Distribution and Remarks. 



Arabia, Persia to Afghanistan. Annual. 



Tropical Asia .ind Australia. Annual. 



Indian Peninsula and Ceylon. 



Indian Peninsula, Ceylon ? 



Arabia. Genus of tropical and south Africa, Madagascar, and 

 Arabia. 



Arabia. Annual. 



Arabia, Persia, Scindh. 



Eastern tropical Asia. Introduced in Africa and America. 



Arabia, India, Ceylon. Annual. Introduced. 



Arabia, Persia. 



Afghanistan, eastwards through sub-tropical and tropical 

 Himalayas. Not known hitherto further west than Afghan- 

 istan. 



Indian Peninsula, Mauritius. Genus is monotypic. 



Persia, Aftghanistan, India. Annual. 



Eastern tropical Asia. Annual. 



Arabia, 



Arabia, north-west India. Represented in Socotra by an endemic 

 variety. Genus referred to on page lx. 



From Syria eastwards to China ; also Australia. Annual. 



Arabia ? Beloochistan, north-west India. 



Arabia (Aden). Tritypic genus ; another species occurs ia 

 Arabia and Nile-land, and the third in Persia and Scindh. 



From Arabia eastwards to northern India. 



Arabia. Annual. 



From Arabia eastwards to India. Annual. 



Indian Peninsula. 



Eastern India (Goozerat). Annual. 



Persia, Beloochistan, Scindh. 



Tropical Asia. 



Indian Peninsula, Ceylon. 



Eastern tropical Asia. 



Eastern tropical Asia and Mauritius. , r> 



India. 



Tropical Asia. 



All the species from the island fall into the categories above mentioned, 

 save half-a-dozen species — Cleome tenella, Hibiscus Solandra, Tillcea pentandra, 

 Cyperus intermedius, C. Tegetum, and C. tenuiflorus — which are plants of 

 tropical Africa and of the Indian Peninsula, but are not reported from the 

 intermediate districts in Asia ; two species of Peperomia, P. Goudotii from 

 Bourbon and P. arabica, recorded from the Cape of Good Hope, Madagascar, 



