96 Dr Gairdner''s Analysis of 



E. Trichodina comosa, n. g. , . . . ^^" 



E. Vibrio rugula, Muller, .... ^^ ^^ 



E. Vorticella convallaria, Muller, . . body ^^ ;j'g 



iS Piriformis. 



In all 148 forms reducible to 113 distinct species, which ex- 

 tend through 51 genera. 95 species comprised in 39 genera, 

 belong to the first class of Phytozoa, the Polygastrica. The 

 other 18 species in 12 genera, belong to the Rotatoria. As- 

 suming the chain of the Urals and the river of the same name 

 as the boundary betwen Europe and Asia, 31 species belong to 

 the former, and 82 to the latter. It will also be seen from an 

 inspection of the table, that 69 species * agree with those which 

 have been described in Europe by Muller, or since discovered 

 at Berlin. The other 44 belong, hke the tropical species, for 

 the most part to European genera. The following genera, 

 which were first discovered on this journey, have been all since 

 detected at Berlin, viz. 



Arcella, Bodo. Trichodiscus. 



Asthma. Eosphora. 



So that there is no genus which can be regarded as peculiar to 

 these regions. 



The genera which contain the greatest number of species al- 

 ways belong to the Phyt. polygastrica, viz. 



6 species of Trachelius. 



7 of Navicula. 



8 " of Bacterina. 

 15 .. of Monas. 



Upon comparing together the African and Russian tables, we 

 find, that the Infusoria which occur, 1. at Petersburg and Bol- 

 goslofsk, in lat. 60° ; 2. at Sinai, in lat. 28° ; and, 3. in Dongola, 



lat. 19°; are: 



Polygastrica — 4. J?o/a/oria— none. 



Cyclidium glaucoma. 

 Kolpoda cucuUus. 

 Paramaecium chrysalis. 

 Trachelius lamella. 



The species which extend over a still greater space, being 

 found at Berlin, the Altai Mountains, Sinai, and Dongola, are : 



• Preceded in the Table by the letter E. 



