GOSSAMER 243 



to ascend, and all that I have seen were so small as to 

 be invisible- without close attention, the body being 

 about an eighth of an inch long or less ; some of the 

 floating Spiders, however, though of small size, arc 

 believed to be adult. 



The question has been raised whether the Gossamer 

 Spiders can, strictly speaking, emit threads from their 

 spinnerets, or whether wind is necessary to draw out 

 the threads. Blackwall l gives us the interesting 

 results of his experiments. " Having procured a small 

 branched twig, I fixed it upright in an earthen vessel 

 containing water, its base being immersed in the 

 liquid, and upon it I placed several of the Spiders 

 which produce gossamer. Whenever the Insects thus 

 circumstanced were exposed to a current of air, either 

 naturally or artificially produced, they directly turned 

 the thorax towards the quarter whence it came, even 

 when it was so slight as scarcely to be perceptible, 

 and elevating the abdomen, they emitted from their 

 spinners a small portion of glutinous matter, which 

 was instantly carried out in a line, consisting of four 

 finer ones with a velocity equal or nearly so, to that 

 with which the air moved, as was apparent from 

 observations made on the motion of detached lines 

 similarly exposed. The Spiders, in the next place, 

 carefully ascertained whether their lines had become 

 firmly attached to any object or not, by pulling at 

 them with their first pair of legs ; and if the result 

 was satisfactory, after tightening them sufficiently they 

 made them fast to the twig ; then discharging from 

 their spinners, which they applied to the spot where 

 1 Linn. Trans., Vol. XV., p. 455 (1827). 



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