91i 
HE SNARE OF THE GIANT WOOD SPIDER {NEPHILA MACULATA). 
BV 
Captain R. W. G. Hingston, I. M. S. 
(Continued from page G49 of this Volume.) 
PART II. 
The Continuation of the Snare. 
one text figure.) 
I resume the architecture of the Nephilu. Her radii are in position, or, at 
least, the frame has been supplied with a system of branching spokes. Now 
comes the next stage, the construction of the hub. In the snare of the Araneus 
this is a distinct and separate act. The spider winds five turns of a slender fila- 
ment around and close to the centre anchoring it at every spoke. Its object 
of course is to strengthen the framework at the point where the radii meet. Now 
look at the snare of the Nephita. We see no sign of any thread just coiled a 
few times around the centre. There is, in an architectural sense, no trace of 
a hub. 
The next stage deserves more careful notice ; it is the construction of the tem- 
porary spiral. Remember the mechanism of the Araneus. Having completed 
her radii, she proceeds to lay down four turns of a spiral round about 
the inner half of her snare. It is but a temporary scaffold. At a later stage 
in the architecture she cuts it completely away. Compare the architecture 
of the Nephita with this. She does not first complete her radii and then apply 
herself to the winding of the coil. I see both operations in progress at the same 
time ; first the placing of a few radii, then the laying of a few turns of the spiral, 
then the resumption of the radii again. The spiral of the Araneus consists of 
about four turns separated widely in the snare. That of the Nephita is a much 
longer and more important structure. I count the turns in the snare under 
observation. They number forty-four. And it is a more closely wound and 
widely distributed filament. It is continued from the centre right out to the 
very rim. Near the centre the turns are very close together ; the distance 
between them being only half an inch. They gradually separate as they 
proceed to the circumference where they are as much as two inches 
apart. 
Again I have no doubt that the reason of the variation in the mode of ar- 
chitecture is the result of the difference in the size of the snares. Four turns 
in the inner half will provide a scaffold of sufficient strength for the few radii 
of a small snare. But this will not satisfy the Nephita. She needs a much 
more elaborate scaffold to support her longer and more numerous spokes. More- 
over, the spiral must be more closely wound and spread throughout the whole 
area of the snare. It is also an excellent provision for the turns to come near 
together at the centre and at the circumference to lie wide apart. For near 
the centre the radii approach one another and there require an additional 
support. t 
I must now enter a word of explanation with respect to the temporary spiral. 
I have called it by this name, though I doubt if I am strictly correct. I imagine 
that it only appears a temporary spiral, while in reality it is something quite 
distinct. Anyone after witnessing the architecture of the Araneus and then 
passing to that of the Nephita, could not but imagine that the two spirals which 
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