202 THE ZOOLOGIST. 



Being essentially a chalk country, many of its valleys and 

 dells are normally dry, but, large areas being covered by the 

 aforesaid post-tertiary deposits, the short grass characteristic of 

 a chalk country is to be found only on parts of comparatively 

 small extent. Numerous woods and copses occur in most 

 parts, and there are also many large private estates and parks, 

 in some of which are many fine Deer. Further, on several 

 of the commons found in most parts of the country there 

 are extensive growths of bracken and furze, which often serve 

 as cover for Pheasants, Partridges, Babbits, Foxes, and other 

 animals. 



There are only a few large sheets of water, and these are 

 connected with the rivers or the Grand Junction Canal; this 

 canal, it may be stated here, runs along or close to the old bed 

 of the Bulbourne (a tributary of the Gade) and that of the lower 

 Gade. On the higher grounds, e.g. on Chipperfield Common, 

 Cholesbury Common, and Berkhamsted Common, and at 

 Wigginton, Hastoe, and various places between Chesham and 

 Berkhamsted, there are many small pools, the depths of which 

 rarely exceed five feet. 



It cannot be said that, in number of species, the aquatic 

 fauna is a rich one, but this disadvantage, from a naturalist's 

 point of view, is compensated for by the remarkable differences 

 between the faunas of the several pools. These differences will 

 be best understood from the following account of the fauna, given 

 in accordance with the method previously expiated. The 

 Kotifers, as already stated, will be dealt w'* v /u first, comrencing 

 with some of the commoner ones. 



BoT^FERA. 



1. Salpina mucronata, Ehren. — In those pools in whi:h there 

 is a large quantity of weed s, especially duckweed, this i one of 

 the commonest Botifers. Trom April to September tie speci- 

 mens are very numerous, and in May and June large lumbers 

 of empty loricas of the samo Botifer are alyo to be fouid. The 

 presence of a large quantit y of duckweed and the situation of 

 the pools at a comparatively low level seem to favour the 

 occurrence of large numbers of S. mucronata. This, a> least, is 

 what my notes suggest. Where these conditions are frund, e.g. 



