Linnaan Society* 345 



of the Galapagos Archipelago, as compared with that of some other 

 Tropical Islands and of the Continent of America." 



The present paper oiFers the deductions which Dr. Hooker has 

 drawn with reference to Botanical Geography from his " Enumera- 

 tion of the Plants of the Galapagos Islands," read during the previous 

 session. He regards the relationship of the Flora to that of the ad- 

 jacent continent as double ; the peculiar or new species being for the 

 most part allied to plants of the cooler parts of America or of the 

 uplands of the tropical latitudes, while the non-peculiar are the 

 same as abound chiefly in the hotter and more humid regions, such 

 as the Islands of the West Indies and the shores of the Gulf of 

 Mexico ; and while on the other hand many of the species, and those 

 the most remarkable (as is likewise the case with regard to the 

 Fauna), are confined to a single islet of the group, and often repre- 

 sented in other islets by similar, but specifically very distinct, con- 

 geners. 



The author commences his memoir with an account of the geo- 

 graphical position, and of some of the most important features of the 

 climate and soil of the Archipelago, chiefly derived from the journals 

 of Mr. Darwin and of some other voyagers, including the unpublished 

 journal of the late Mr. T. Edmonstone. This is followed by an 

 Enumeration of the Naturalists who have explored it in the order of 

 the dates of their respective visits, including Mr. Cuming, Mr. David 

 Douglas, Dr. Scouler, Mr. Macrae, Mr. Darwin, Admiral Du-Petit- 

 Thouars and Mr. Edmonstone. The total number of species brought 

 together from these various sources amounts to 244, of which 202 

 ar^ flowering plants and 28 ferns. All of these, excepting perhaps 1 7, 

 natives of Charles Island (the only inhabited one), are truly indige- 

 nous, but it is probable that this is only an approximation to the true 

 number. Under any circumstances, however, the Flora is extremely 

 poor when compared with that of other tropical islands of equal, or 

 even of smaller, extent ; the Cape de Verd Islands, scarcely so well 

 explored, yielding upwards of 300 species on a soil quite as sterile ; 

 and the Sandwich and Society groups being very much richer, 

 although further detached from any great continent. 



Dr. Hooker next proceeds to review the Flora under three distinct 

 heads ; first with reference to the proportion borne by each of the prin- 

 cipal Natural Orders to the whole Flora, and its relations to the Flora 

 of the neighbouring continent and of other islands somewhat similarly 

 circumstanced. Secondly, he treats of the Flora of the Galapagos 

 as divisible into two types ; the West Indian (including Panama), to 

 which the plants common to other countries and some dubious spe- 

 cies almost universally belong; and the Mexican and temperate 

 American, or that under which the great majority of the peculiar 

 species rank. Thirdly, he notices the most singular feature in the 

 vegetation of the group, namely that the several islets are tenanted 

 for the most part by different species, many of which are, however, 

 represented by allied species in one or more of the other islets. 

 Under each of these heads Dr. Hooker enters into minute statistical 

 details, accompanied by extensive research and careful comparisons. 



