ee ee eee 
J - 
COMPOSITE SNARES AND SECTORAL ORBS. 145 
web of the Orbitelarie ; or, shall we say, a tendency to run tangent from 
its own typical form into that of the established type of Epeira? On one 
small bush, where perhaps a dozen Zilla atricas were domiciled, I found 
no less than four orbs with completely rounded webs. In one of these, a 
very rare circumstance indeed, I found that the trapline occupied a sector 
below the median line of the web. In this interblending of spinning habit 
Zilla shows the peculiarity already noted in the closely related species of 
the genus Epeira, Epeira triaranea. 
This colony afforded some very interesting illustrations of the strong 
tendency to variation in the manner of forming the trapline. Ordinarily, 
as has been shown, the trapline of orbwebs consists of a single cord, which 
connects the hub of the orb with the feet of the spider lodged 
a in her retreat above and at the side of her snare. As a 
ne fi rule, the end which is attached to ‘\ the hub divides into 
several branches, obviously giv 
in the way of telegraphy. Sometimes 
will be observed near the feet of the spi 
the trapline. But generally 
holds the single line within 
Labyrinth spider, the trap 
threads which diverge near 
by the foot, and converge 
the ordinary rule in the gen 
is probably the one most 
series of drawings presented . 
depart from this habit. Fig. 
ing greater facility 
one or more branches 
der, where she clasps 
one fore foot reaches out and 
the claws. In the case of the 
line consists of a number of 
the point where they are clasped 
toward the hub, and thus reverse 
us Epeira. The single trapline 
commonly used by Zilla, but the 
will show how widely she can 
134, for example, shows the 
trapline with a number of diverging lines toward the foot 
of the spider at S, the whole system forking about the mid- 
dle of the line, T, and being ee een supported by another Y-shaped 
line still nearer to the hub. — Zilla. At Fig. 135 the trapline has 
assumed the rude outline of an hour glass. Five or six deltations grasp 
the meshed hub, and these lines converge about the middle of the trapline 
system, from which point they diverge toward the spider’s nest and the 
surrounding leaves, upon which the snare is supported. The feet of the 
spider at S are extended beyond the leafy nest, and grasp at least two 
lines of the system. Fig. 136 shows still further divergence from the 
original type. Here the hour glass, if I may continue the figure, appears 
to have been cut into two, and the ends well separated by a bent line, in 
the midst of which is a triangular patch swung to adjoining leaves. The 
‘two fore feet of the proprietor are thrust from her tubular nest and grasp 
the principal diverging lines of her system. 
I have observed similar arrangements in the trapline system of Epeira 
domiciliorum whose orbs were swung upon a barbed wire fence inclosing the 
grounds of Woodland Cemetery. The question, of course, naturally arose, 
