The look of the obstacle, therefore, does not count; dull or brilliant, drab or coloured: these are details of no importance; the thing that matters is that there should be a passage to allow the grubs to enter.
Though hatched outside, at a distance from the coveted morsel, the new-born worms are well able to find their refectory.

As they release themselves from the egg, without hesitation, so accurate is their scent, they slip beneath the edge of the ill-joined lid, or through the passage cut by the knife.

Behold them entering upon their promised land, their reeking paradise.
Eager to arrive, do they drop from the top of the wall?
Not they! Slowly creeping, they make their way down the side of the jar; they use their fore-part, ever in quest of information, as a crutch and grapnel in one.

They reach the meat and at once instal themselves upon it.
Let us continue our investigation, varying the conditions.

A large test-tube, measuring nine inches high, is baited at the bottom with a lump of butcher's meat.