168 THE ZOOLOGIST, 



they differ very much in the degree to which they are ex- 

 posed to sun and wind. To what extent these differences 

 influence the rotiferan faunas it is very difficult to say, but 

 there are other differences which undoubtedly influence the 

 faunas to a great extent. So far I have not made a detailed 

 examination of these differences. It may be stated, however, 

 that the flora of the moats is much more varied than the floras 

 of the pools, and, while the waters of Langleybury Pool and the 

 moats are modified by the products of decomposition of vast 

 numbers of leaves fallen from trees and shrubs of various kinds 

 which border them, the water of Parsonage Farm Pool contains 

 small quantities of sodium chloride and other salts derived from 

 surface drainage. 



When such differences have been examined in detail, a con- 

 sideration of them in relation to the differences in the rotiferan 

 faunas will probably suggest a maze of perplexing questions, but 

 if attempts to solve these lead to no definite results, there will 

 remain a number of statements of fact which might be of 

 interest to other observers. For the present, however, further 

 consideration of the rotiferan fauna of the country of the Chess 

 and Gade will be deferred, and the next series of notes will deal 

 with the Entomostraca. 



