Vlll INTRODUCTION. 



and consequently I have not been able to introduce 

 more of the important matter to be found in that 

 excellent memoir.* 



Finding, on my arrival in Gibraltar, in the latter 

 part of 1843, an interesting and almost unexplored 

 field for botanical research, in accordance with the 

 suggestions of many valued friends, I undertook the 

 formation of a Catalogue of Plants growing on the 

 rock and in its neighbourhood. The want of books 

 protracted my labours, and it was not till I happily 

 made the acquaintance of M. Prolongo, of Malaga, 

 the friend and frequent companion of Ed. Boissier, in 

 his tour in Spain, that I was able to pursue my 

 researches with comparative facility. This gentle- 

 man, with great liberality and kindness, lent me 

 several works from his botanical library, for which 

 I cannot feel too much indebted. My duties as a 

 medical officer of the garrison of Gibraltar for the 

 short period of two years, prevented my making 

 distant excursions into the interior of Spain or Bar- 

 bary. The few I made were confined to the imme- 

 diate vicinities of Gibraltar, Malaga, Granada, and 



* Quarterly Journal of the Geological Society for 

 February, 1846. 



