302 ME. J. ball's spicilegiijm tlor^ maroccan^. 



Southern Spain, Grreece, and Asia Minor. On tlie arenaceous and 

 porphyritic rocks of the Ait Mesan valley we found to a great ex- 

 tent the same endemic species afterwards gathered on the schistose 

 and calcareous rocks of Djebel Tezah, at least 30 miles distant. 



Another fact worth noticing is, that, among a considerable num- 

 ber of new specific forms, no new generic type has yet been found 

 in the Great Atlas. 



But in my opinion the most singular point about the Great- 

 Atlas flora is the presence of a large number of the common 

 species of Central Europe, both annual and perennial, coupled 

 with the fact that many of these are not species that have proved i^; 



their power of adapting themselves to different climatal condi- 

 tions, and that many of them have no nearer habitat than the 

 mountains of Central or Southern Spain, while others must be 

 sought at a still greater distance. , 



The conclusion to which I am led by a consideration of the facts 

 is the same that I have derived from rather long observation of 

 the mountain-vegetation of Central and Southern Europe — namely, 

 that it is impossible to explain the facts without admitting that 

 a large portion of our present flora is relatively very ancient, 

 and that the species had assumed their present characters at least* 

 as early as the Miocene epoch. ^-^ 



I ought not to omit mentioning that two years after our visit 

 two German naturalists, MM. Eein and Eritsch, were able to 

 make a short expedition in the Great Atlas, nearly following our 

 footsteps. They were not exclusively engaged in collecting plants ; 

 but they have deposited at Kew specimens of most, if not all, the 

 plants found by them. Having been able to examine these, I 

 have enumerated their t^pecimens in the following catalogue. 



In determining the specimens of our collections I have been 

 materially assisted, in regard to the Orchide^, by my friend Prof. 

 H. G. Eeichenbach. The friendly aid and assistance of Professor 

 Oliver and Mr. J. G. Baker have been frequently invoked by me ; 

 and to the latter I am especially indebted for his thorough know- 

 ledge of the Liliacese and Amaryllideae of the Mediterranean , 

 region, which he kindly contributed for my benefit. To Mr- 

 Bentham, it is needless to say that in any case of doubt or diffi- 

 culty I never applied in vain. The resources of his unequalled 

 knowledge are always at the service of the younger and less-gifted 

 workers in the field of science ; and I cannot better close than by 

 expressing the sense of affectionate regard with which I acknow- 

 ledge his guidance. 



