Hydatinaea,] THE INFUSORIA. 367 



styles ; the foot furcated. The strong styles, or bristles, 

 are situated between the clusters of cilii, and, probably, 

 act as teeth ; the body is very short, and broad anteriorly, 

 tapering to a point posteriorly, so that it resembles a cone. 

 Internal longitudinal muscles exist in all the species; 

 those of the foot are seen in three species : the cesophagal 

 head is large, with single-toothed jaws, and exists in all 

 the species ; but in two only is the whole chewing appa- 

 ratus distinctly seen. The thin cesophagal tube is long in 

 two species, short in the rest ; it leads to a simple, wide, 

 conical, alimentary canal, which has two roundish, or, in 

 one species, conical pancreatic glands. The ovarium is 

 rolled up like a ball; male contractile vesicles exist in 

 three, and sexual glands in two species ; transverse vessels 

 (four to ten) are visible in two species ; and a respiratory 

 tube, probably, in S. pectinata and tremula, a tremulous gill 

 being also present in the former. The principal nervous 

 matter is a knotty mass surrounding the head of the reso- 

 phagus, and in the middle of it is a large, roundish, red 

 eye. In S. pectinata three pair of ganglia and strong 

 nerves are also seen. 



621. SYNCH AETA pectinata. The comb-bearing Syn- 

 chaeta. Body short, conical, with two styles, and two 

 crest-like horns anteriorly. "Are these horns," asks 

 Ehrenberg, " respiratory tubes, as in Polyarthra, and in 

 Anuraea?" The liveliness and uniform transparency of 

 this animalcule render it difficult to distinguish its 

 various organs. The styles arise from the muscle of the 

 cesophagal head, and appear as if belonging to simple- 

 toothed jaws. Fig. 422 represents a view of this creature 

 (dorsal side) ; in it the organization, described under the 



