2 7 



following the Olenellus Limestone at the Wrekin, and by the beautiful 

 detailed work of Mr. Cobbold in the Comley area near Caradoc. 



Lapworth directed the work of the fossil collectors for the 

 Geological Survey and for Cambridge University, and large col- 

 lections were obtained for these institutions from Cambrian and 

 Ordovician rocks. 



Lapworth carried his mapping downward into the Uriconian 

 and other volcanic rocks of the Wrekin and Caradoc, and the 

 neighbouring areas, and I believe his large scale maps of these areas 

 are extant. Most of the Shropshire and Montgomeryshire work is 

 summed up in a communication to the Geologists' Association on 

 the occasion of their visit to the region in 1894 (49) and given in 

 fuller detail in the contribution on Shropshire to ' Geology in the 

 Field ' (67, 1910). 



4. The Hyolithes Limestone. 



These discoveries gave renewed interest to the Nuneaton area. 

 When Dr. Stacey Wilson noted the probable existence of calcareous 

 beds and indications of fossils along the junction of the quartzites 

 and shales, this line was thoroughly searched. A new excavation 

 revealed the presence here of a limestone bearing remains of 

 Hyolithes, Coleoloides, and horny brachiopods. A comparison of 

 these fossils showed that many of them occur in association with 

 Olenellus in America and elsewhere. But Lapworth was cautious in 

 correlation, and he stated : *" The exact horizon of the Hyolithes 

 zone of the Midlands cannot yet be regarded as absolutely fixed. 

 That it is Lower Cambrian is regarded as more than probable. 

 That it answers to any special part of the Olenellus zone has yet 

 to be determined." 



In 1898, however, when he wrote his masterly account of the 

 Geology of the Birmingham District, on the occasion of the visit 

 of the Geologists' Association, he and Miss Wood (Dame Ethel 

 Shakespear) reviewed the evidence, and, after comparison with 

 the Olenellus and Etcheminian faunas of America and Scandinavia, 

 he was able to go a little further and say : f" The general facies 

 of the curious fauna of this Hyolithes Limestone speaks strongly 

 in favour of the view that it is of Lower Cambrian age, answering 

 in part to the Olenellus zone of other regions." This view has been 

 subsequently verified by the finding of Olenellus in the shales just 

 above the limestone. Mr. Illing also has confirmed and extended 

 Lapworth's conclusions as to the age of the Stockingford Shales, 

 which prove to contain Lower, Middle, and Upper Cambrian 

 faunas, an approximately complete succession. 



As his knowledge of the Scottish quartzites had been instru- 

 mental in suggesting to him as a working hypothesis that the 



* 53, P. 232. t 55, P. 343- 



