266 DESCRIPTION OF {Polygaslrica. 



panulate body, the frontal portion broad, truncated, and 

 the margin expanded. The colour is white, the pedicle is 

 branched, the division being subumbellate. The stomach- 

 cells are easily discerned, when indigo is mixed with the 

 water, and the mouth is thus indicated by the particles 

 becoming approximate near it. The reception of coloured 

 food into the oesophagus is observable ; but its passage 

 from one digestive sac to the other is so quick, that the 

 alimentary canal has not been seen and traced as a con- 

 tinuous tube ; it is similar to the act of swallowing in large 

 animals, the food not remaining for any length of time 

 in the oesophagus before it passes into the stomach. 

 Figu7-es 240 to 245 represent tree-like clusters, except 

 fig. 244, which is a single free animalcule. Figures 240 

 and 241 are only slightly magnified, the latter is con- 

 tracted. In figures 242 and 245, as also the free pedicle, 

 fig. 243, the muscle is very distinct. This muscle was 

 first observed by Mr. Varley. Size 1-5 70th to l-430th ; 

 ova granules 1 -24000th. 



Genus XCII. Epistylis. The pillar Animalcules. — 

 Vorticellina with a rigid pedicle, either simple or branched, 

 and having all the corpuscles of the same figure ; or, in other 

 words, they are Vorticella or Carchesei with a rigid pedicle, 

 without its internal muscle. The pedicle, or stalk, appears 

 to be a hollow tube. Their polygastric structure, and the 

 situation of the united mouth and anal opening, are easily 

 demonstrated by the employment of coloured food. In 

 E. plicatilis, the whole course of the alimentary canal can 

 be seen. The granular ova, says Ehrenberg, have been 

 measured in several species ; a contractile bladder, and a 

 short band-like male gland, are observable in many ; the 



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