Spiders. 381 



while tight drawn in a right line. It further appeared to 

 us, that the first thread proceeded from the pair of spin- 

 nerets nearest the head, while the floating thread came 

 from the outer pair, though it is possible in such minute 

 objects we may have been deceived. That the first was 

 continuous with the second, without any perceptible join- 

 ing, we ascertained in numerous instances, by catching the 

 floating line and pulling it tight, in which case the spider 

 glides along without attaching another line to the glass ; 

 but if she have to coil up the floating line to tighten it, as 

 usually happens, she gathers it into a packet and glues the 

 two ends tight together. Her body, while the floating line 

 streamed out, remained quite motionless, but we distinctly 

 saw the spinnerets not only projected, as is always done 

 when a spider spins, but moved in the same way as an 

 infant moves its lips when sucking. We cannot doubt, 

 therefore, that this motion is intended to emit (if eject or 

 project be deemed too strong words) the liquid material of 

 the thread ; at the same time, we are quite certain that it 

 cannot throw out a single inch of thread without the aid of 

 a current of air. A long-bodied spider will thus throw out 

 in succession as many threads as we please, by simply blow- 

 ing towards it ; but not one where there is no current, as 

 under a bell-glass, where it may be kept till it die, without 

 being able to construct a bridge over water of an inch long. 

 We never observed more than one floating thread produced 

 at the same time ; though other observers mention several. 



The probable commencement, we think, of the floating 

 line, is by the emission of little globules of the glutinous 

 material to the points of the spinnerules perhaps it may 

 be dropped from them, if not ejected, and the globules 

 being carried off by the current of air, drawn out into a 

 thread. But we give this as only a conjecture, for we could 

 not bring a glass of sufficient power to bear upon the spin- 

 nerules at the commencement of the floating line. 



In subsequent experiments we found that it was not in- 

 dispensable for the spider to rest upon a solid body when 

 producing a line, as she can do so while she is suspended 



