400 EVENINGS AT THE MICROSCOPE. 



movements to allow me to identify them before, or to per- 

 ceive anything else than their swift motion and oval form ; 

 but this attraction, causing them to become still, allowed 

 me to perceive their singular and beautiful structure. Each 

 consists of an oval vase open at the top, the margin of 

 which is cut into a number of little points ; the sides are 

 marked by a series of ribs, which run down longitudinally, 

 and are crossed by other transverse ones; the rounded 

 bottom is furnished with three short points, so that the 

 whole reminded me of a barrel with its staves and hoops, 

 set on a three-legged stool. Within the body, which is 

 colourless, are seen small dark spots which are probably 

 the stomach-vacuoles. Thus I identified these little barrels 

 with Coleps hirtus of Ehrenberg, but I found no record of 

 their carnivorous propensities. One after another whirled 

 into the field, and after a few gyrations became stationary 

 at the head of the half-born Euchlanis, just as I have seen 

 vultures gather one by one to a carcase. Very soon there 

 were a dozen or fifteen of them, some of which were ever 

 shifting their places, and some were playing around, or 

 revolving on their longitudinal axes. I found that their 

 object really was to prey on the soft parts of the creature 

 just excluded from the egg ; for, by carefully watching one, 

 I distinctly perceived particles of the flesh fly off, as it 

 were, and disappear in the body of the Coleps. The 

 appearance was that of steel filings drawn to a magnet, for 

 the mouth of the Coleps was not in actual contact with the 

 flesh ; and therefore, I suppose, the surface having been in 

 some way ruptured (which I could see it was), the loose 

 gelatinous atoms were sucked off by a strong ciliary cur- 

 rent. They did not attack any other part, and after having 

 continued their murderous occupation about ten minutes, 

 they one by one departed. The ciliary motion of the 

 Euchlanis ceased immediately after it was first attacked, 

 and I suppose it was soon killed, for it did not increase in 

 size in the least afterwards. When the Colepes left it, a 



