1 10 CHAPTER OF VARIETIES. 



FLOATING ISLANDS. In the province of Colchagna, M. Gay found, 

 near Tagnatagua, an extensive lake, " in which," he says, " I saw, 

 for the first time, that singular phenomenon, a great number of float- 

 ing islands directed entirely by the winds. Having studied a certain 

 number of these islands with great care, I observed that they were 

 composed entirely of the remains of several vegetables, and especially 

 of the stalks of Typha, Arundo, Convolvulus, &c., interlaced in a 

 thousand different ways, and forming a species of net-work, on which 

 had been driven many other plants ; these latter, decaying, deposited 

 a mould, which increased from day to day, and became at length 

 capable of receiving shrubs and even trees of a moderate size. Their 

 form is generally circular, and their thickness four or six feet ; the 

 greatest part of which is sunk in the water. 



As this lake is nearly desert, and surrounded by very high moun- 

 tains, birds of every genus and species repair to it in flocks, and add 

 to the truly picturesque aspect of its environs that gay and animated 

 air which is so pleasing to the landscape painter ; it was, indeed, 

 both curious and agreeable, to see at one time this prodigious quantity 

 of birds navigating peaceably among these floating islands ; some of 

 them, such as the black-necked swan, the numerous varieties of ducks, 

 trails, cocks, &c., seemed to prefer the middle, while the ibis, spoon- 

 bill, flamingo, hyalus, and an infinity of other wading birds, with a 

 beak more or less slender, wandered by the banks, quietly seeking 

 objects for food, at the bottom of the water. I visited for several days 

 the greater part of these isles, which enriched me with several very 

 interesting plants, such as Convolvulus, Ranunculus, Islricularia, 

 and other European genera, and, above all, with a series of beautiful 

 nests and eggs, objects which are so neglected by travellers, and yet 

 possessing such real interest in the natural history of birds." 



ON THE ANIMALCULJE FOUND IN WATER, &c. There is, perhaps, 

 no more surprising fact in the study of nature, than the existence of 

 such minute beings as these. That each of these creatures which are 

 invisible to the naked eye, unaided by the microscope, possesses a per- 

 fect set of organs, as well calculated to perform every function as those 

 of superior animals, those who have attentively studied can testify. 

 But the most extraordinary fact, and one which (I confess) fairly puz- 

 zles me, is the theory of their production. I have made some trifling 

 experiments on this subject but can form no satisfactory conclusion. 

 I made an infusion of hay in spring water, and after letting it remain 



