410 APPENDIX E. 



sentatives of tropical India. Some will no doubt yet be dis- 

 covered in Marocoo, especially south of the Atlas ; and it is not 

 unreasonable to suppose that such have crossed Africa in a sub- 

 tropical latitude, and thus reached the Canaries under conditions 

 now operating. 



The most remarkable are the following. The genera in 

 capitals have not hitherto been found in Marocco : — 



Polycarpon succulentum 

 ViSNBA Moccanera 

 Gymnospoeia cassinoides 

 Trigonella hamosa 

 Senecio flavus 

 Cbeopbgia diohotoma 



Campylanthus salsoloides 

 Teaganum nudatum 

 APOLLONIAS barbusana 

 Euphorbia Forskahlii 

 DEACiENA Draco 



Of the above hardly any have been found west of the Levant, 

 or anywhere between Egypt and the Canaries, except, possibly, 

 in Southern Algeria. Traganum must be reckoned as an African 

 and Oriental desert type, and will probably be found in South 

 Marocco ; but Ceropegia is mainly Indian, as is Gymnosporia 

 {Gatha cassinoides, Webb). Campylanthus consists of the Cana- 

 rian species, of a variety or closely allied one in the Gape de Verde 

 Islands, and of a third which extends from Southern Arabia to 

 Scinde. The nearest ally of the Apollonias {Phoebe barbusana, 

 Webb) is a Ceylon tree ; and Visnea is nearly allied to the 

 Malayan genus Anneslea. Dracaena Draco is the most in- 

 teresting of all in the list ; for, though the genus abounds in 

 tropical Africa, the Canarian form, which is also a native of 

 the mountains of the Cape de Verde Islands, has only one near 

 ally, the D. Ombet, which is confined to Abyssinia, Southern 

 Arabia, and the intervening Island of Socotra. 



b. The peculiar species representing American types in- 

 habiting the Canaries or Madeira, but not found in Marocco, are 

 in some respects even more remarkable than the Oriental. 



They belong to the following genera : — 



Bowlesia^ {Drusa oppositifolia, DC), Clethra, five species 

 of Bystropogon, and Gedronella. Of these Bowlesia is other- 



' Whilst this sheet was passing through the press, I am informed 

 that M. Cosson's collectors have found Bowlesia in South Marocco. No 

 doubt this is another case of that accidental difEusion of Macaronesian 

 species alluded to by Ball. (See p. 405.) 



