Description

Immediate dispatch from Somerset. Nice book in great condition. Pages in excellent condition. No notes or highlighting. See images. Fantastic book.

About the book >.>.> The fossils of the British Caenozoic rocks illustrated in the first handbook of this series consist largely of well-preserved gastropod and bivalve shells that can be collected only at a relatively small number of localities. Most of them belong to genera still living although their present-day relatives may live in distant regions. The Mesozoic fossils such as those depicted here are more diverse and widely known because the formations in which they occur are more extensive (frontispiece map) and reflect a greater variety of marine and non-marine environments. Gastropod and bivalve molluscs are abun- dant among the fossils but there are also representatives of many other groups including ammonites and brachiopods which are extinct or relatively rare at the present day. Moreover some of these groups particularly the ammonites which became extinct at the end of the Mesozoic showed rapid evolutionary changes in their morphology unlike anything seen in British Tertiary faunas. Hence they demonstrate even more clearly than do the Tertiary shells how the study of fossils enables the geologist to determine the relative ages of rocks found in different districts. It was in fact his intimate knowledge of the Mesozoic fossils of south-western England that led the pioneer geologist William Smith to enunciate clearly for the first time the principle that geological formations can be identified by the organic remains they contain. (LL)