INFUSORIA. 



399 



Meanwhile I will tell you the tragical and lamentable his- 

 tory of just such an embryo as this, that, was eaten up 

 before it was born, under my own eye. One of the depre- 

 dators was a very amusing animalcule, which is sufficiently 

 scarce to make its occurrence a thing of interest, espe- 

 cially to a young microscopist, as I was at the time. 



A large egg of (as I believe) Eucltlanis dilatata had been 

 laid during the night on a leaf of Nitella, in the live-box. 

 When I observed it, the 



transparency of the shell 

 allowed the inclosed ani- 

 mal to be seen with its 

 viscera, which occasion- 



ally contracted and ex- 

 panded ; the place of the 

 mastax I could distinctly 

 make out. The cilia were 

 vibrating, not very ra- 

 pidly, but constantly, on 

 the front, where there 

 was a vacant space between the animal and the shell. 

 From seven a.m. when I first saw it, I watched it for about 

 eight hours, without perceiving any change ; but at that 

 hour having withdrawn for a short time, I perceived on 

 my return that a portion of the animal was outside the 

 shell. The appearance was that of a small colourless 

 bladder oozing out at an imperceptible aperture ; and this 

 oval vesicle quickly but gradually increased, until it was 

 half as large as the egg itself. A little earlier than this 

 point, the cilia were seen on the front or lower side of the 

 excluded portion, and these began to wave languidly in a 

 hooked form. They thus seemed much longer and more 

 substantial than when rotating in the perfect animal. 

 When excluded to the extent just named, some little crea- 

 tures that were flitting about found it, and began to 

 assemble round it. These were far too rapid in their 



COLEPS AND CHIL01IONAS. 



