344 MOTIONS OF INSECTS. 



flights than usual, and seek the upper regions of the at- 

 mosphere ; and that the spiders catch them there, ap- 

 pears by the exuviae of gnats and flies, which are often 

 found in the falling webs 2. Yet one would suppose 

 that insects would fly high at all times in the summer 

 in serene warm weather. Perhaps the flight of some 

 particular species constituting a favourite food of our 

 little charioteers — the gnats, for instance, which we 

 have seen sometimes rise in clouds into the air ''—may 

 at these times take place ; or the species of spiders that 

 are most given to these excursions, may not abound in 

 their young state — when only they can fly — at other 

 seasons of the year. 



Whether the same species that cover the earth with 

 their webs produce those that fill the air, is to be our 

 next inquiry. Did the appearance of the one always 

 succeed that of the other, this might be reasonably con- 

 cluded : — but the former, as I lately observed to you, 

 often occurs without being followed by the latter. Yet, 

 since it should seem that the aerial gossamer, though it 

 does not always follow it, is always preceded by the 

 terrestrial, this warrants a conjecture that they may be 

 synonymous. Two German authors, Bechstein'^ and 

 Strack'', have described the spider that produces gossa- 

 mer in Germany under the name of Aranea oblextrix'^. 

 But it is not clear, unless they have described it at dif- 

 ferent ages, when spiders often greatly change their 

 appearance, that they mean the same species. The 

 former describes his as of the size of a small pin's head, 



■ Ray's Letters, 42. Lister De Araneis, 8. ^ Vol. I. 2d lid. 1 15. 



"Lichtenberg und Voight Magazin. 1789. vi. 53 — , 



* N&ve Schriften der Naiurforsch. &c. ISIO. v. Heft 41-56. 



