LIVER ROT OF SHEEP, AND BIONOMICS OF 
LIMNAEA TRUNCATULA IN THE 
ABERYSTWYTH AREA. 
By Chas. L. WALTON, M.Sc. (Wales). 
(Departments of Zoology and Agriculture, University College 
of Wales, Aberystwyth.) 
(With 5 Text-figures.) 
CONTENTS. 
PAGE 
I. General Notes on Area.232 
Introduction.232 
Topography of the Aberystwyth Area .... 233 
Natural Divisions of the Area ...... 236 
Methods of Work ........ 237 
II. Liver Rot ......... 238 
Distomum hepaticum in the Area ..... 238 
Methods of Combating the Liver Fluke .... 239 
III. Observations on the Bionomics of Limnaea truncatula 
The Distribution of L. truncatula and L. peregra 
Food of L. truncatula and L. peregra .... 
Movements and Migrations ...... 
Effects of Temperature ...... 
Oviposition ........ 
Drought, and its effects upon the Snail 
Local Rainfall Data ....... 
Sequence of Life History ...... 
Effects of Drought upon the Ova .... 
Field Observations upon the Life History . 
Roadside Distribution and its Economic Effects 
Cercariae ......... 
243 
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I. General Notes on the Area. 
Introduction. 
In the autumn of 1913 I was instructed to commence a Survey of 
the Agricultural Zoology of the Aberystwyth Area, and in particular 
to study the Liver Rot of Sheep and the bionomics of Limnaea truncatula 
