84( DISCKEPANCIES. 



bably not quite correct ; I fear it destroys the poetry of 

 this story, that feather- and dirt-feeding, and parasitic in- 

 sects and spiders should be the first inhabitants of newly- 

 formed oceanic land." * 



The occurrence, far out on the boundless sea, of crea- 

 tures which we habitually associate with the land, is a 

 phenomenon which interests even those who are little 

 observant of natural history. Visits of land-birds to 

 ships have often been noticed by voyagers, and that not 

 of those species only which are known to make long 

 transmarine migrations, but of small and feeble-winged 

 races, such as finches and warblers. It is much more 

 remarkable, however, to see insects under such circum- 

 stances ; yet examples of this are not wanting. Mr 

 Darwin expresses his surprise at finding a considerable 

 number of beetles, alive and apparently little injured, 

 swimming in the open sea, seventeen miles off Cape 

 Corrientes, at the mouth of the La Plata. These may 

 have been carried down by a river, especially as several 

 of them were water-beetles ; but this will not account for 

 aerial insects taking a sea voyage. The same naturalist 

 was surrounded by flocks of butterflies of several kinds, 

 (chiefly of the genus Colias,) ten miles ofl" t]je same coast. 

 They were in countless myriads, so that the seamen cried 

 that it was " snowing butterflies,"' extending as far as the 

 eye could range ; and, even with a telescope, it was not 

 possible to see a space free from butterflies. The day 

 had been fine and calm, and so had the day before ; so that 

 * Naturalist's Voy., chap. i. 



