This animalculum is perfectly cylindrical, very pellucid, of a crystalline appearance; it is marked with very fine longitudinal furrows, and has generally two transparent globules, one placed below the middle, the other near the extremity of the body; on the other side are five smaller ones, which are oval. The top is dilated, with the corners rounded like the spatula, or instrument for spreading plaisters. It has a wavering kind of motion, folding the spatula variously, yet retaining its general form. Müller mentions his seeing it once draw the spatula into the body, and keep it there for two hours, when it again appeared.
50. Exchelis Pupula.
A cylindric enchelis, the fore-part papillary.
The fore-part is protuberantly round, and rather opake, the hind-part pellucid, both extremities obtuse, furnished with a papillary finger-shaped head, the hinder part marked with a transparent circle, or circular aperture. The fore-part filled up with moveable molecules, which are more scarce in the hinder-part. It has a rotatory motion on a longitudinal axis, and moves through the water in an oblique direction. It is to be found in dunghill water in November and December.
51. Enchelis Pupa.
E. ventricoso cylindrica, apice in papillam producta. Enchelis forming a kind of ventricose cylinder, with a small nipple proceeding from the apex.
It is not unlike the preceding animalculum, but is much larger; the anterior end not so obtuse, the nipple gradually formed from the fore-part, all but this end is opake, and filled with obscure particles: it has no transparent circle, as was observed in the enchelis pupula. Its motion is exceeding slow.
V. VIBRIO.
Vermis inconspicuus, simplicissimus, teres, elongatus. An invisible worm, very simple, round, and rather long.