438 THE MICROSCOPE. 



gular class of objects are Biatoma flocculosum, being rather 

 oblong-looking, and joined "to each other at opposite cor- 

 ners : they are sometimes grooved on each side. (Fig. 225, 

 No. 17.) The "Swollen Eunotia" is generally about 

 from the 11th to the 200th of an inch in length: a 

 groove, widest in the centre, and tapering off to the ends, 

 passes along its centre on both sides ; it has curved lines 

 proceeding from it. So wonderfully close are these lines 

 or ribs, that as many as eight of them have been 

 counted in the space of the 1200th of an inch. They are 

 usually found when alive adhering to a branch of some 

 weed that forms the green coating over stagnant waters. 

 They propagate by self-division ; a slight line running 

 down the centre marks where the separation will occur, 

 on each becoming perfectly developed as a distinct crea- 

 ture ; and thus they grow and separate, filling the earth 

 with their flinty shells. 



Gallionella sulcata is found in many parts of North 

 America ; it somewhat resembles the cylindrical box for 

 spices, which was at one time so common among good 

 housewives; scientifically, it is described as consisting of 

 chains of cylindrical bivalve loricse, having their outer 

 surfaces marked or furrowed with longitudinal striae ; short 

 joints may occasionally be seen, having their ends upper- 

 most, the depth of the furrows being shown on the margin ; 

 within the mai'gin is a thin transparent rim having ra- 

 diating striae. Sometimes as many as forty will be found 

 joined together. (Fig. 225, No. 9.) The Gallionella received 

 its designation from a celebrated French naturalist named 

 Gaillon, it is often termed the Box-chain Animalcule, and 

 when the flinty case is seen lying on its face, it much re- 

 sembles a coin. These living infusoria are found in almost 

 all waters, and are stated to be so rapid in their growth, 

 that one hundred and forty millions will by self-division 

 be produced in twenty-four hours. A species named the 

 Striped Gallionella was discovered by Dr. Mantell near 

 London ; the same species is also found in the ocean. 

 Sometimes the chains are three inches long; their size is 

 from the 14th to the 400th part of an inch. 



Professor Quekett, in the catalogue we have referred to, 

 describes an " earth from Bohemia, particularly rich in 



