62 GKNET?AL HISTORY OF 



Professor Siebold not only rojocts the class Polygastrica, but uses 

 the temi Infusoria in a veiy limited signification, intending by it 

 only those animalcules moved by cilia. To express the beings 

 known by Ehrcaiberg as Pohjgastrica, except the Bacillaria and 

 Closterina, he has devised the word Protozoa; and he thus arranges 

 them : — 

 I. Class. — Ixfttsoeia, Animals moving by cilia. 



Order I. — Astoma, Infusoria without a mouth. 



Family 1. — AstasioBa — Genera, Amhlyophis, Euglena, 



Chlorogonium. 

 Family 2. — Peridinoea — Genera, Peridinium, Glenodinium. 

 Family 3. — Opalincea — Genus Opalina. 

 Order II. — Stomatoda, Infusoria with a mouth. 

 Family 1 . — Vorticellina — Genera, Stentor, Trichodina, 



Vorticella, Epistylis, Carchesium. 

 Family 2. — Ophrj'dina — Genera, VaginicoJa, Cothurnia. 

 Family 3. — Enchelia — Genera, Actinophrys, Leucophrys, 



Prorodon. 

 Family 4. — Trachelina — Genera, Glaucoma, Spirostomnm, 

 Trachelius, Loxodes, Chilodon, Phialina, 

 Bursaria, Kassida. 

 Family 5. — Kolpodea — Genera, Kolpoda, Paramecium^ 



AmphiJeptus. 

 Family 6. — Oxytrichina — Genera, Oxytricha, Stylonychia. 

 Family 7. — Euplota — Genera, Euplotes, Mimantophorus, 

 Chlamidodon. 

 II. Class. — Rhizopoda, Animals mo^^ng by variable processes. 

 Order I. — Jlonosomatia. 

 Family 1 . — Amcebcea — Genus A7noeha. 

 Family 2. — Arcellina — Genera, Arcella, Difflugia, Gromia, 

 Miliola, Euglypha, Trinema. 

 Order II. — Polysomatia — Genera, Vorticialis, Geoponus, 

 Nonionina. 

 REcnoN XYIII. — Geographical Distribution of Polygastrica, their 

 relative ahundance, ^c. — The Polygastrica, as understood by Ehrcnberg, 

 are the most widely diffused of all organized beings. From the icy 

 region of Spitzbcrgen, near the North Pole, to the utmost limit 



