A HISTORY OF DEVONSHIRE 



Amongst the fossils of the Eifelian limestones and slates are the 

 following : Phacops latifrons^ Grypheeus punctatus, Cyphaspis, Rhynchonella 

 procuboides, Kayseria lens, Pentamerus galeatus, Productus subacukatus, 

 Spirifer speciosus, S. curvatus, Atrypa reticularis, A. aspera, A. desquamata, 

 Cyrtina whidbornei, Heliaster Jiliciformis and Heliolites porosus. 



The Ashprington volcanic series occupies an area of about ten 

 square miles, between Dittisham and Totnes, and consists of shalsteins 

 (embracing tuffs and lavas), sheared diabases often vesicular, with 

 intrusive masses of aphanitic and porphyritic diabase. The eruptions 

 began during, and just prior to, the deposition of the Eifelian limestones 

 and probably continued into the Upper Devonian period, as we find the 

 limestone, which is mostly of coralline growth, interrupted by local 

 vulcanicity in the upper part near Goodrington and at Black Head, 

 Torquay, and at lower stages in different parts of the limestone districts, 

 according to their proximity to local centres of vulcanicity in action at 

 different times during the period represented by the volcanic rocks of 

 the Ashprington series. 



The limestone masses passed out irregularly on their borders into 

 slates or slates with volcanic rocks. The Torquay and Babbacombe 

 bedded limestones, partly represented by the Marldon, Little Hempston, 

 and Darlington limestones, belong to the series immediately overlying 

 the Eifelian, and above these come massive limestones such as those of 

 Lummaton, Kingskerswell, the Daisons. In fact, where calcareous 

 growth has been uninterrupted, the upper beds have a more or less 

 massive character, and the lower a more or less evenly, or distinctly, 

 bedded aspect. The south Devon limestones are locally dolomitic. They 

 are rich in Stromatopora, favositid corals, and Alveolites. Brachiopods are 

 most plentiful in the lower and upper horizons. 



The Continental boundary between the basement {Rhynchonella 

 cuboides) zone of the Upper Devonian and the Stringocephalus, or Middle 

 Devonian, limestone should be taken in the upper massive limestones. 

 In the Lummaton limestone the shelly material is very restricted but 

 very prolific ; in it Whidborne records the discovery of io6 specimens 

 oi Rhynchonella cuboides and 25 oi Stringocephalus burtini \ at Woolborough 

 42 of the former, and 1 8 of the latter. Rhynchonella cuboides has also 

 been found at Barton near Lummaton, at Langs Copse in the Bradley 

 Woods, and at Lower Dunscombe. The Ramsleigh (with Acervularia 

 pentagona), Petitor, Ilsham, Kersewell Down, upper part of Kingsteign- 

 ton (north of), and upper part of the Brixham limestones belong to the 

 same category, in which the Goodrington {Favosites cervicornis) bedded 

 limestones must also be included, and perhaps part of the Plymouth 

 limestone near Plymstock station. 



Upper Devonian.— The relations of the Middle and Upper Devonian 

 strata are rendered much more complex by the resistance offered by the 

 Dartmoor granite to the forces which compressed and contorted them. 

 Thus from Plymouth northward to Tavistock is a series of slates very 

 unfossiliferous which from their characters seem mainly to belong to the 



