436 Scientific Intelligence. 
The author divides all the microscopic forms connected with geology 
into the following classes : 
A. Silicious, B. Caleareous. - 
Class 1. Polygastrica, Class 5. Polythalamia, 
+ olycistine, ee litharia, 
* 3. Phytolitharia, 
‘© 4, Geolitharia. ai . 
he classes just mentioned are treated of in the present volume with 
reference Ist, to Freshwater formations; 2d, to Marine deposits; 3d, 
to minute life transported by the atmosphere. The published portion 
h noun 
of the text which amo 
a 
specimens, and with a few exceptions represent the objects as magnifie 
which we overlooked. We must however beg leave to differ from the 
‘author with regard to the origin of the plants which he evidently SOP- 
poses to have grown at the bottom of the ocean, and which he has repre- 
* 
