Other spiders again, such as _Theridion_,[49] suspend by a long and delicate cord of silk a minute balloon, scarcely larger than a seed-pearl, containing their eggs, which sways to and fro in the lightest breath of air. But admirable as these cocoons and geometrical snares are, the homes of these and of spiders generally do not exhibit much contrivance or ingenuity, or cannot at any rate be ranked in the same category as those of the trap-door spider. But it may be asked, why should we admire the one more than the other, since it is clear that the most squalid and mean-looking nest exactly serves the purpose of its occupant, whether for shelter or defence, and in many cases a spider might even say with truth that as for her home it would not be so safe if it were not so dirty. [Footnote 49: _Theridion variegatum_ (Bl.). _Ero tuberculata_, Koch.] But the answer is simple: the trap-door spider's dwelling is to that of common spiders what the Mont Cenis tunnel is to other tunnels, and something besides. What delights us is to see how by clever contrivance and great perseverance new and multiplied difficulties have been overcome, and dangers avoided, and the interest aroused is exactly proportionate to the amount of these difficulties and dangers. It is hoped that the following pages and their accompanying illustrations will vindicate the claims of these spiders to the marked attention and admiration which is here asserted to be their due as architects and engineers. There is but one British or North European representative of the _Territelariæ_--namely, _Atypus piceus_ (or _Sulzeri_),[50] and this creature does not appear to deserve the name of trap-door spider, for in three nests which M. H. Lucas kindly showed me, preserved at the Jardin des Plantes at Paris, the mouth of the tube was destitute of any covering. I gathered from what I saw, and from what M. Lucas told me, that these nests [which he had taken in the neighbourhood of Paris], consist of a silk tube from eight to ten inches long, of which about one inch only at the lower extremity penetrates the earth, the remainder being carried upwards in an irregular and sinuous course among the stems and leaves of small plants and grasses to which it is attached. When the tube is removed from these supports it collapses, and appears like a rather coarsely woven ribbon-shaped strip of silk.[51] [Footnote 50: Unless it should prove, as Prof. Ausserer suggests, that the British _Atypus_ is distinct from the Continental, when it would bear the name of _Atypus Blackwallii_. (Ausserer, l. c. p. 17).]