238 Transactions. —Zoology. 
in the individual, but the power of adaptation to circumstances, and of 
selection to suit the emergencies as they arise, take the case of a nest in 
bare burnt ground; such ground is invariably coated with a thick covering 
of herbage before the fire runs over it; it may not be very rank and long, 
but it must be close and continuous, or the fire will not run onit. The 
spider, in such circumstances, must have had its trap-door planted thick 
with herbage also, and would know nothing of roots or pieces of stick, or 
bits of half-burnt grass, and yet in the altered condition of the surface, when 
rain and wind have done their work in removing the loose surface loam and 
exposing the roots and stumps of woody plants and burnt grass leaves, 
there you find this master conjuror alter his mode and materials of conceal- 
ment to suit the altered conditions in which he finds himself placed, 
Specimens of Trap-doors not the same as when obtained. 
It would be too tedious, after this general discussion, to describe in 
detail each one of the twenty-eight trap-doors now before you, though each 
one has some peculiarity of detail which makes it differ from every other, 
and supplies it with an interest of its own. It will be better, I think, to 
select one or two of those differing most, and to which special interest 
attaches ; reminding you that the shaking and jolting of a journey of 100 
miles over rough New Zealand roads has not tended to improve their ap- 
pearance. 
Description of ateue deceptive Trap-doors. 
Trap-door No. 6 is an instance where brown-clayey loam is the sole 
covering of the lid, to correspond with the same bare soil around. The web 
forming the lid is thin, tough, and leathery, and of a brown colour ; but it is 
thickened by the covering soil, cemented on the-outside. It is small, but 
fits accurately. This trap-door is the trap-door of nest No. 4, and spider 
No. 2, alluded to before as found at the foot of the corner of a stable. The 
ground is rather sloping, but the trap-door is constructed level, and for this 
purpose a portion of the minature bank is excavated out, half-an-inch deep 
at the back part where the hinge is placed. This is a further illustration of 
what I have referred to in page 229, of the Oamaru species never taking 
advantage of a slope of a bank, or of a sod-wall, to assist the trap-door in 
closing to, as mentioned by Moggridge and others as characteristic of the 
species in other parts of the world. Itis also an illustration of the case alluded 
to in page 229, where water must have been caught, and must have lodged 
round about the mouth of the nest. But yet, in this very peculiarity of 
formation, we fave an instance of how observant these insects are of pecu- 
liarities of situation, and of their power of exact imitation of these pecu- 
liarities. This nest was situated exactly under the line of drip from the 
stable-roof. The roof is shingled with what are colonially known as Hobart 
