Dec. 1833. AERONAUT SPIDERS. 187 



Beagle was to windward of the Cape de Verd Islands, and 

 when the nearest point of land, not directly opposed to the 

 trade- wind, was Cape Blanco on the coast of Africa, 370 

 miles distant.* 



On several occasions, when the vessel has been within 

 the mouth of the Plata, the rigging has been coated 

 with the web of the Gossamer Spider. One day (No- 

 vember 1st, 1832) I paid particular attention to the phe- 

 nomenon. The weather had been fine and clear, and in 

 the morning the air was full of patches of the floc- 

 culent web, as on an autumnal day in England. The ship 

 was sixty miles distant from the land, in the direction 

 of a steady though light breeze. Vast numbers of a small 

 spider, about one-tenth of an inch in length, and of a dusky 

 red colour were attached to the webs. There must have 

 been, I should suppose, some thousands on the ship. The 

 little spider when first coming in contact with the rigging, 

 was always seated on a single thread, and not on the floccu- 

 lent mass. This latter seems merely to be produced by the 

 entanglement of the single threads. The spiders were all of 

 one species, but of both sexes, together with young ones. 

 These latter were distinguished by their smaller size, and 

 more dusky colour. I will not give the description of this 

 spider, but merely state that it does not appear to me to be 

 included in any of Latreille's genera. The little aeronaut as 

 soon as it arrived on board, was very active, running about ; 

 sometimes letting itseK fall, and then reascending the same 

 thread ; sometimes employing itself in making a small and 

 very irregular mesh in the corners between the ropes. It 

 could run with faciUty on the surface of water. When dis- 

 turbed it Ufted up its front legs, in the attitude of attention. 

 On its first arrival it appeared very thirsty, and with exserted 

 maxillee drank eagerly of the fluid ; this same circumstance 



* The flies which frequently accompany a ship for some days on its 

 passage from harbour to harbour, wandering from the vessel, are soon 

 lost, and all disappear. 



