Close to the road hung the under jaw of a Horse, having six fore teeth, much worn and blunted, two canine teeth, and at a distance from the latter twelve grinders, six on each side. If I knew how many teeth and of what peculiar form, as well as how many udders, and where situated, each animal has, I should perhaps be able to contrive a most natural methodical arrangement of quadrupeds[42]. [42] Here the Linnæan system of _Mammalia_ seems first to have occurred to the mind of its author. I could not help remarking that the very best fields of this part of the country, in which from six to ten barns commonly stood, were almost entirely occupied with turfy hillocks producing nothing but Hair-moss, _Polytrichum_, and that quite dried up. Some of the barns were evidently in a decayed state; which made me suspect this condition of the land to be an increasing evil, and that it had formerly been more productive than at present. Indeed some of these tumps were so close together that no grass had room to grow between them. If the cause of this evil, and a cure for it, could be discovered, the husbandman would have reason to rejoice. Wherever these hillocks abounded, the earth seemed to be of a loose texture, consisting of either mud or clay. When I stepped upon them they gave way, and when cut open they appeared all hollow and unsound. I conceive the frost to have a great share in their formation, which when it leaves the ground causes a vacuity, and the turf, loosened from the soil, is raised up. The insects which occurred to my notice this day, besides those above mentioned, were the following: A black _Ichneumon_, like a Humble Bee, with club-shaped antennæ four lines long, and blueish wings. Its mouth armed with a pair of toothed forceps. Thorax hairy, with several smooth spots interspersed. Abdomen depressed, ovate, rough at the base with greyish hairs, and furnished with a series of scales beneath, see fig. b. Feet pale red, otherwise the general colour of the insect is black. It lives on the willow. (This appears to be the _Tenthredo lucorum_, a species not preserved in the Linnæan cabinet.) [Illustration] A small _Papilio_, of the fritillary tribe, with one silver mark underneath of the form of a shield. See it among those of Petiver collected in Portugal. (This must surely be _Papilio C album_.) A greyish Butterfly with feathered antennæ, whose female has no wings. See Swammerdam. (_Phalæna antiqua._) An elegant little blackish Butterfly, besprinkled with snow-white spots like rings, smooth and polished on the under side, was very plentiful in the paths. A black _Tipula_ was running over the water, and turning round like a _Gyrinus_ or Water Flea. (_Cimex lacustris._) In the wells, the _Swammerdamia_ of Swammerdam and Lister ran about with great velocity. Among these was a very minute insect, which I could not ascertain.