vi PREFACE. 
talents and disinterested zeal of the above distinguished authors, 
could not have been undertaken, had it not been for the libe- 
rality of the Lords Commissioners of Her Majesty’s Treasury, 
who, through the representation of the Right Honourable the 
Chancellor of the Exchequer, have been pleased to grant a sum 
of one thousand pounds towards defraying part of the expeises 
of publication. 
I have myself published separate volumes on the ‘Structure 
and Distribution of Coral Reefs; on the ‘Volcanic Islands 
visited during the Voyage of the Beagle ;’ and on the ‘Geology 
of South America.’ The sixth volume of the ‘ Geological Trans- 
actions’ contains two papers of mine on the Erratic Boulders 
and Volcanic Phenomena of South America. Messrs. Water- 
house, Walker, Newman, and White, have published several 
able papers on the Insects which were collected, and I trust that 
many others will hereafter follow. The plants from the southern 
parts of America will be given by Dr. J. Hooker, in his great 
work on the Botany of the Southern Hemisphere. The Flora of 
the Galapagos Archipelago is the subject of a separate memoir 
by him, in the ‘Linnean Transactions,’ The Reverend Professor 
Henslow has published a list of the plants collected by me at 
the Keeling Islands; and the Reverend J. M. Berkeley has de- 
scribed my cryptogamic plants. 
I shall have the pleasure of acknowledging the great assist- 
ance which I have received from several other naturalists, in the 
course of this and my other works ; but I must be here allowed 
to return my most sincere thanks to the Reverend Professor 
Henslow, who, when I was an under-graduate at Cambridge, 
was one chief means of giving me a taste for Natural History, 
—who, during my absence, took charge of the collections I sent 
home, and by his correspondence directed my endeavours,—and 
who, since my return, has constantly rendered me every assist- 
ance which the kindest friend could offer. 
Down, Bromley, Kent. 
June, 1845, 
