1920.] 
Smith. — Parasitism in New Zealand Spiders. 
13 
PARASITISM IN NEW ZEALAND SPIDERS. 
By W. W. Smith, New Plymouth. 
When visiting Kotorua some years ago as a member of the Scenery- 
preservation Commission I spent two Sundays collecting insects, chiefly 
ants, in the immediate vicinity of the boiling mud-pools, fumaroles, and 
geysers in that active thermal region. When turning over stones and heaps 
of decayed vegetation to procure ants secreted beneath them, I observed 
some large spiders run out from under a decayed log which I had turned 
over. The log lay near some almost boiling thin mud, on to which one 
of the spiders ran when disturbed. During the afternoon of the same 
day I detected some large spiders secreted under their webs constructed 
under a small ledge of rock which was sprayed with hot steam and 
vapour blown over it by the fresh wind from the geyser. Unfortunately 
I did not collect for identification any of the spiders seen in these hot 
habitats. 
On my second visit to the district I noted that several species of 
spiders were plentiful on the stunted vegetation growing near the hot 
steaming pools situated on the east side of the main road at Ohinemutu. 
On a calm overcast day many of the webs are laden with the moisture of 
steam from the hot pools. The power of these spiders to endure the 
intense heat under the natural conditions I have stated interested me 
much, and induced me to try similar experiments artificially with native 
species of spiders of the Taranaki District, with quite unexpected results. 
For several years I have been collecting spiders of certain genera for 
an English collector, who informed me that he was “ very much interested 
in New Zealand spiders, and the valuable papers by A. T. Urquhart 
describing them.”* When out collecting I carry a large tin box, with small 
sliding lid cut in the large lid, into which I put species of spiders not 
required for despatch to England. During an illness twenty months ago 
I devoted some time each day during the last week to experiments with 
spiders in water heated to various temperatures. I used, and continue 
to use, a large goldfish-globe with thin pane-glass lid. On the bottom of 
the globe is a layer of clean-washed coarse light-coloured sand, and on it 
are placed some large pieces of white marble. The bottom is first covered 
with cold water, and this is raised to the required heat by pouring hot 
water slowly into the globe to avoid cracking it. The spiders experimented 
with are first placed on the cold water. 
The species of spiders inhabiting the margins of the hot pools and 
fumaroles at Kotorua consisted of individuals representing several genera. 
The species collected in the public park here and placed in the globe of 
hot water to test their heat-bearing powers consisted of three Araneus, 
two Theridion, and one Liny'phia. I placed them all on the largest piece 
of marble. The temperature of the water was 146° F. The vapour from 
the hot water condensing on the inner side and airtight lid prevented the 
spiders from being seen from the outside. On raising the lid after ten 
minutes’ test, I noted that one of the Araneus had moved from the largest 
* Trans. N.Z. Inst., vols. 18 to 25. 
