CHARLES DARWIN TO J.S. HENSLOW. East Falkland Island, March, 1834. ...I am quite charmed with Geology, but like the wise animal between two bundles of hay, I do not know which to like the best; the old crystalline group of rocks, or the softer and fossiliferous beds. When puzzling about stratifications, etc., I feel inclined to cry "a fig for your big oysters, and your bigger megatheriums." But then when digging out some fine bones, I wonder how any man can tire his arms with hammering granite. By the way I have not one clear idea about cleavage, stratification, lines of upheaval. I have no books which tell me much, and what they do I cannot apply to what I see. In consequence I draw my own conclusions, and most gloriously ridiculous ones they are, I sometimes fancy...Can you throw any light into my mind by telling me what relation cleavage and planes of deposition bear to each other? And now for my second SECTION, Zoology. I have chiefly been employed in preparing myself for the South Sea by examining the polypi of the smaller Corallines in these latitudes. Many in themselves are very curious, and I think are quite undescribed; there was one appalling one, allied to a Flustra, which I dare say I mentioned having found to the northward, where the cells have a movable organ (like a vulture's head, with a dilatable beak), fixed on the edge. But what is of more general interest is the unquestionable (as it appears to me) existence of another species of ostrich, besides the Struthio rhea. All the Gauchos and Indians state it is the case, and I place the greatest faith in their observations. I have the head, neck, piece of skin, feathers, and legs of one. The differences are chiefly in the colour of the feathers and scales on legs, being feathered below the knees, nidification, and geographical distribution. So much for what I have lately done; the prospect before me is full of sunshine, fine weather, glorious scenery, the geology of the Andes, plains abounding with organic remains (which perhaps I may have the good luck to catch in the very act of moving), and lastly, an ocean, its shores abounding with life, so that, if nothing unforeseen happens, I will stick to the voyage, although for what I can see this may last till we return a fine set of white-headed old gentlemen. I have to thank you most cordially for sending me the books. I am now reading the Oxford 'Report' (The second meeting of the British Association was held at Oxford in 1832, the following year it was at Cambridge.); the whole account of your proceedings is most glorious; you remaining in England cannot well imagine how excessively interesting I find the reports. I am sure from my own thrilling sensations when reading them, that they cannot fail to have an excellent effect upon all those residing in distant colonies, and who have little opportunity of seeing the periodicals. My hammer has flown with redoubled force on the devoted blocks; as I thought over the eloquence