226 Transactions. — Zoology. 
spider tunnels down a comparatively deep hole, through the surface soil 
into the clay or differently coloured subsoil beneath. This subsoil it 
brings up last, and generally carries to some distance from its hole (from 
one to eighteen inches), and forms a spoil-bank there ; the excavated stuff 
is all cemented in a peculiar way, afterwards described, but this does not 
prevent the rain from gradually washing it away, more or less, thereby dis- 
colouring the surface soil, for a short distance, with the differently coloured 
sub-soil. For instance, if the surface loam be black, and the subsoil 
yellow clay, there is no difficulty whatever in detecting them, as the yellow 
mark remains, even after the spoil-bank has been washed away; and, as 
the spoil-bank is always on the lower side of the nest, all you have to do 
when you see such a mark, is to look from six to eighteen inches above it, 
according to the lay of the ground, and it will be strange indeed, if you do 
not detect somewhere, a little round ring on the ground, or amongst the 
herbage, marking the lip of the trap-door, where it fits to the beveled 
mouth of the nest. I do not say you will find every one this way, forsome _ 
are so skilfully concealed, as to defeat every search made for them, and 
others (specimens of some of which are before you), were only discovered 
by accident, and would never, I believe, have been discovered in any other 
way; the above, however, gives a clue which aids immensely in the search 
for them. 
Nests and their distinctions. 
The nests are in reality, tunnels of varying size, dug into the ground, 
and lined more or less with silk of varying thickness and consistency, and 
with a lid or trap-door hinged to the mouth. Mogeridge distinguishes four 
types of trap-door nests (see page 79), in the world at large, and names 
them. First, the single-door cork nest, or shortly, the cork nest; second, 
the single-door wafer nest; third, the double-door unbranched nest; 
and fourth, the double-door branched nest. The distinction here drawn, 
between the first and second type consists in the thickness of the door; 
the cork nest, having a thick door beveled at the edges and fitting tight ; 
the wafer nest, having a thin door. J am inclined to think, that so far as 
the Oamaru species are concerned, this distinction will not hold good, that 
is, on the supposition that the individuals forming a colony in any one 
place are likely to be of the same species, for, notwithstanding that I had 
this distinction always in view, I never was able to detect any such marked 
differences in the thickness or fitting of the lids in different localities, or in 
different colonies in the same locality, as to be specially noticeable. Cork 
nests and wafer nests were found in: all localities, and, in fact, amongst 
the scores of nests I haye examined, this distinction does not hold good. 
Doors of all degrees of thickness are to be found, and of all degrees of neat- 
