MICROSCOPIC OBJECTS. 



young they are much smaller, and being then perfectly translucent, 

 are highly interesting microscopic objects. They are found in 

 abundance in the months of March and April, at the surface of 

 shallow pools of clear water which contain aquatic plants. 



The back of this animalcule is protected by a tender and 

 transparent shell, the belly being naked and membranous. Seen 

 in profile it resembles a tortoise, but, as shown in the figure, it has 

 the form of a horse-shoe. It has four feet, and two antennae 

 attached to the inferior part of the body, and radiating from a 

 common centre. Placed in the middle of the head, between the 

 two antennae, 6, are the mouth and the single eye, a, the latter 

 being black, and set in a square orbit of a deep crimson colour. 

 Each of the antenna? has four articulations, and is furnished with 

 bristles at its extremity. The feet, c c, are divided at the second 

 joint, and terminate in strong pincers. The peristaltic motion of 

 the alimentary canal can be distinctly perceived with the micro- 

 scope, by observing the dark lines which run along the body of 

 the animalcule. On each side of this canal are placed the 

 ovaries, d, which, when they are fully developed, are distin- 

 guished by their dark colour. The satyr swims by sudden 

 impulses, moving the feet rapidly, and sometimes appears to 

 slide along the internal surface of the vase. 



4. The animalcule represented in fig. 4, and reproduced from a 

 Fig 4> drawing by Dr. Goring, 



is the linceus sphericus 

 of Miiller, miscalled mon- 

 oculus minutus by Lin- 

 nasus, since it has two 

 eyes sufficiently apparent. 

 The figure is reproduced 

 from the Microscopic 

 Cabinet of Mr. Pritchard, 

 where the animalcule is 

 described. 



The shell or cuirass, 

 which is quite trans- 

 lucent, consists of a single 

 piece, without any per- 

 ceptible articulation. It 

 possesses, however, suf- 

 ficient elasticity to allow the animal to open it at will, after 

 the manner of a common mussel. The two edges of the 

 opening are seen in the figure at o, the figure being understood 

 to present a profile of the object. The two eyes, , have 

 different magnitudes, and their black colour presents a striking 

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