ON THE LOWER PALEOZOIC ROCKS OF ENGLAND AND WALES. 12. 



B. Excavations in the Comley Area. 



Excavation No. 2.— 200 Yards South of Comley Quarry, Reo'pened. 



The discovery of fragments of Olenellus, sensu lata in the Black Lime- 

 stone of the Cwms (see above), rendered additional work advisable at the 

 same horizon in the Quarry Kidge at Comley, the full section of which 

 is given {op. cit.) in the report to the Dublin Meeting. 



The Black Limestone was uncovered and some highly fossiliferous 

 blocks obtained ; these yielded at least two species of trilotiites referable 

 to the MesonacidcB ; fragments provisionally referred to Oryctocephalus, 

 which is a genus found in both Middle and Lower Cambrian of America ; 

 a species of Microdiscus that appears to be undescribed ; and a number of 

 specimens of HyoUthidce. All of these require critical study before they 

 can be specifically determined. 



Excavation No. 4. — North sfiir of Little Caradoc, 200 yards 

 west-south-west of the Comley Quarry, reopened.^ 



The old trench was considerably widened and deepened at the site 

 of the beds marked «2 in tbe Dublin Report, to which the Mottled Beds 

 (b) of the section of the Road Quarry (see above) bear a strong lithological 

 resemblance. The grits with rounded quartz grains were found to con- 

 tain pebbles of pre-existing rocks and also fragments of Brachiopoda, 

 some of which are referred to Obolella (?) groomii and a species of Micro- 

 mitra. 



Excavatimi No. 5. — Hill House Ridge. Nwth End.'' 



Here further work in quarrying rough stone for walling had been 

 done by the occupier of the land, and from the material of the Hill House 

 Grits thus exposed a single cranidium of Paradoxides intermedins Cobbold 

 was obtained. Fossils that can be identified are very scarce in these beds* 



P. intermedins occurs typically in the Comley Breccia Bed.^ The 

 Hill House Grits may therefore be regarded as belonging to the same 

 faunal horizon as the Breccia Bed, which has been proved to be equivalent 

 to some part of the Swedish P. tessini zone. 



Excavation No. 57. — Caradoc Dingle. 



In a little wooded hollow called Caradoc Dingle about half-way be- 

 tween the Comley Quarry and Robin's Tump soft shales are exposed 

 at one or two places in the bed of the brook. At one point a rib of rock 

 some eight or ten yards long projects through the soil, and from it in 1901 

 a few brachiopods were found on the occasion of an excursion of the 

 Liverpool Geological Society. A trench was cut across this ril> and the; 

 following section was exposed : 



Wiist End of the Scclion. 

 h... Bluish shale, much crushed and fractured, about .3 feet seen. (Brachio- 

 poda were obtained from this bed by Prof. Lapworth and Mr. Rhodea 

 in 1892 or earlier.) ft. in. 



Interval where no rock is seen of about 12 



6|. Shale rather harder but much crushed 8 



ttj. Band of pyritous grit 2 



" Rey. Brit. Assoc. 1908, Dublin, 1909, p. 238. 

 ' Rep. Brit. Assoc. 1908, Dublin, 1909, p. 240. 



» Rep. Brit. Assoc. 1912, Dundee, 1913, pp. 139, 140, and Q.J.O.^. vol. Ixix. 1913, 

 pp. 27-44. - . 



