Ganurgs.— Description of Trap-door Spiders’ Nests. 801 
Arr. XLII.— Description of Trap-door Spiders’ Nests from California and from 
Western Australia in the Christchurch Museum. By. R. Guus, F.L.8. 
Plate XIII. 
[Read before the Otago Institute, 9th October, 1877.] 
In November last, when in Christchurch, I had the opportunity, through 
the kindness of Dr. Haast, of examining four trap-door spiders' nests from 
California and two from Western Australia, which are deposited in the 
Canterbury Museum, and which I was informed have never been examined 
or described. Each nest or trap-door has special features of its own which 
I will point out afterwards, but there is a very marked distinction between 
the Californian nests and the Western Australian, and between each of them 
and our New Zealand species. The Californian nests have all thick doors 
bevelled at the edge, and fitting tight into the mouth—the outside of the 
trap-door being level and coincident with the surface around—they are, in 
_ fact, true “ cork nests.” The South Australian ones have the mouths of the 
nests raised above the surface around; they are really on little hillocks or 
protuberances of the ground and have the trap-door fitting on to the top of 
the^mouth as a eap overlapping all round and raised in the centre like 
miniature tea or coffee-pots with lids to them. A reference to my paper on 
the New Zealand species * will show that they are quite different from either 
of these types. In that paper I stated that I was inclined to think the 
distinetions laid down by Moggridge between cork nests and wafer nests 
did not hold good so far as the Oamaru species is concerned. My examina- 
tion of these nests has revealed to me that what Moggridge referred to as 
cork nests was something quite different probably from what I understood. 
The distinction between cork nests and wafer nests rests mainly on the 
thickness of the door, and as he gives no measurements as a guide, I fell 
into the mistake of thinking that the extremes of the thicknesses would be 
within reasonable limits as compared with the size of the nest, and hence I 
said that * doors of all degrees of thickness are to be found and that this 
distinction does not hold good." I find now that these Californian nests 
have their doors so excessively thiek in proportion to their size as at once 
to justify the distinetion of cork nests, and therefore that our New Zealand 
species, with all their varying thicknesses of door, are all wafer nests. 
These foreign nests, now about to be deseribed, are also very much shorter 
than those of our New Zealand species, and in this they approach more 
nearly to the Jamaica nest in our own museum, and described at the end of 
my paper mentioned above. It is believed that the ultimate classification 
* Trans. N.Z. Inst., VIIL, Art. XXXI. 
