144 AMERICAN SPIDERS AND THEIR SPINNINGWORK. 
stretched their characteristic webs diagonally across to the hand rail. It 
thus happened that as many as a dozen or fifteen snares would be built 
out from the same cornice or moulding, their upper foundations occupying 
the same horizontal plane, but diminishing in length as they approached 
the angle made by the post and the hand rail. The wedge shaped space 
thus defined was almost completely filled with spinningwork, the orbs vary- 
ing a good deal in size, but being alike in structure. 
The position was a good one for trapping insects, which fly in vast 
numbers over the surface of the streams, but I could not but wonder 
whether some of the spiders occupying the interior snares were not sore 
put to it to pick up an honest living, and might not have been constrained 
to resort to cannibalism. However, I saw no raids “ower the border,” 
notwithstanding the traditions of the Scottish site, but all the aranead 
clans seemed to be dwelling in peace. 
I had a fine opportunity one summer of studying the spinning habit 
of Zilla atrica at Annisquam, Massachu- 
setts. Many of this species were colonized 
upon the spacious grounds and 
surroundings of the place where 
I was lodged. They were domi- 
ciled upon the chicken coops and outbuild- 
ings, upon the shrubbery, and in consider- 
able numbers upon the boat house on the 
very verge of the inlet. In the latter po- 
sition their snares were swung just above 
the point of high tide, and they were very 
busy capturing the insects that flew around 
and above the water, and defending them- 
selves from vigorous colonies of Epeira patagiata domiciled in the same site. 
I noticed an occasional tendency among these Zillas to spin a full 
round orb. For example, in one colony of fourteen, all the nests were 
sectoral except one. In another of fifteen, fourteen were sectoral, and one 
had a complete orb. I could observe no obvious reason from 
Excep- the nature of the location why this difference should appear. It 
asian evidently is characteristic of the genus. Zilla callophyla, a 
Webs. Huropean species, can usually be recognized among the British 
Orbweavers by the open sector, which characterizes its web. 
This peculiarity, however, does not always exist, as webs formed by young 
individuals, probably of the same brood, are occasionally found within a 
short distance of each other, some with the characteristic free radii, others 
constructed after the usual Epeira type.1 There appears, thus, in both 
hemispheres to be a tendency in this genus to revert to the typical round 
Zilla 
atrica. 
> 
‘> 
Ty 
SN 
Lory 
Fias. 134, 185. Complex or branched traplines 
of Zilla. S, the spider; S.R., sectoral radius. 
1 Staveley, “British Spiders,” page 247. 
