STUDIES IN ENGLISH GEOLOGY 



By R. S. BASSLER 

 Head Curator, Department of Geology, U. S. National Museum 



Field-work by members of the department of geology is usually 

 devoted to the acquisition of new study and exhibition material, but 

 occasionally some of this time must be employed in a search for 

 knowledge to increase the scientific value of the existing collections. 

 This is particularly true with regard to many of the invertebrate 

 fossils collected by early students, who, for various reasons, did not 

 record their geological formation and geographic locality with the 

 accuracy required for the more detailed studies of the present day. 

 Several decades ago a general label for the occurrence of a fossil was 

 deemed sufficient, the identification of the species being regarded as 

 the most important information. Fortunately, a study of the rocks 

 in the identical or general localities from which the fossils were de- 

 rived will often supply this missing information. During previous 

 trips abroad, I visited classic localities on the continent partly for 

 this purpose ; but a vacation trip to England during the past summer, 

 with the opportunity of traveling about quickly by automobile, per- 

 mitted a study of some well-known southern England fossil areas 

 extending from Cornwall on the west to the chalk cliffs at Dover. 

 With London as a base, excursions were made to various parts of 

 the English Lowlands, with brief intervals spent at the British 

 Museum of Natural History checking the formation and locality 

 occurrences of certain Paleozoic crinoids, and at the neighboring 

 Geological Museum at South Kensington, inspecting the newly in- 

 stalled physical geology exhibits. 



The field studies included first the Subcarboniferous Mountain 

 limestone of the Avon gorge and the Mendip Hills areas near Bristol, 

 which have produced many fossil crinoids. A visit to the great 

 gorge through these hills at the latter locality (fig. 18) showed 

 extensive outcrops of the crinoid-bearing strata, although specimens 

 were not as common as the exposures would indicate. The gorge is 

 of interest to the general public for its caves and a cleft in the rock 

 which is said to have inspired the hymn "Rock of Ages," when its 

 author was sheltered there during a storm. Arrangements were 

 completed for securing casts of type specimens of certain little- 

 understood crinoids from this area preserved in the Bristol Museum, 

 in order that their structure now can be ascertained. 



