THE CLAY HAIRWORM. 
226 
inspect the clay hairworm (gordius argillaceus), yet it is 
a very curious creature. We find it at the bottoms of 
drains and ditches, chiefly in the spring ot the year. 
Its color is a pale yellow ; and it appears like some long 
vegetable fibre, or root, coiled up and twisted together. 
The whole body of the animal consists of numerous 
annulations, or rings, by means of which it has the 
power of contracting its substance, as it has likewise 
of extending it, until it becomes nearly a foot in length, 
and smooth as a wire. The extreme points are trans- 
parent and tapering, formed of apparently harder ma- 
terials than the body. The designation of most of our 
small land and water creatures, in the economy of crea- 
tion, i^ very obscure ; and owing to the places they 
frequent, and the secrecy of their actions, amidst mud 
and vegetation, we have little opportunity of becoming 
acquainted with their habits. This hairworm, however, 
is rather less mysterious in its movements than some 
others ; and there is cause to suppose that its chief oc- 
cupation is that of forming perforations and openings 
in clayey soils, admitting by this means water to pervade 
the mass, and open it ; the finer roots of vegetables 
then find entrance, and part it yet more, or decay in it, 
and meliorate and fertilize the substance. 
Wonderful as all the appointments and endowments 
of insects are, there is no part of their economy more 
extraordinary than the infinite variety of forms and 
materials to which they have recourse in the fabrication 
of their nests ; and, as far as we can comprehend, their 
expediency for the various purposes required. Among 
those, with which I am acquainted, none pleases me 
more than that of a solitary wasp (vespa campanaria), 
which occasionally visits us here. It is not a common 
insect ; but I have met with their nests. One was fixed 
beneath a piece of oak bark, placed in a pile ; another 
was pendent in the hollow of a bank of earth. The 
materials, which composed these abodes, seemed to be 
particles scraped or torn from the dry parts of the willow, 
sallow, or some such soft wood, and cemented again by 
animal glue, very similar in texture to that provided by 
the common wasp, which makes great use of the half- 
