132 DESCRIPTION OF [Polygastrica. 



extremely minute. Ehrenberg remarks, " that only one of 

 the species has been satisfactorily determined, and that 

 their organic relations are altogether so occult, that our 

 judgment respecting them must unavoidably be left in a fluc- 

 tuating state." InB. triloculare, organization is discoverable 

 to the extent of a vibratory proboscis, a granulated mass 

 within the body of the creature, and its faculty of spon- 

 taneous division. The only animal endowment common 

 to all the species is an active and voluntary power of 

 locomotion. 



A magnifying power below 500 times linear will not 

 exhibit the divisions or transverse lines where the indi- 

 viduals or links of which the wand-like cluster is composed 

 are united. I have generally met with them around decom- 

 posed vegetable matter, on the surface of water containing 

 chara, &c. 



89. Bacterium trilocula7'e. The three-celled Bacterium. 

 — Chain consists of from two to five animalcules, of an oval 

 form, developed in short cylinders, generally about three 

 times as long as their diameter, and marked with trans- 

 verse lines. Ehrenberg has observed not more than five 

 links together nor less than two, a single animalcule never 

 having fallen under his notice. By throwing a little 

 colouring matter into the water, an evident vibration may 

 be perceived in it near the anterior portion of the animal- 

 cule ; and upon a very close inspection, a simple filiform, 

 though short proboscis, is seen, which, in the larger speci- 

 mens, is one-third the length of the body, and in the 

 smaller, one half. The motion of this creature is tremu- 

 lous, or slowly revolving upon its longitudinal axis. 

 Found in the water of bogs. Length of cluster, 1 -4800th 



