SPECIES OE CXADOPHOPvA. 



177 



EXPLANATION OF PLATE VII. 



Fig. 1. Bictyonema vermstum, sp.no v. : 1 a, natural size; 1 b, magnified 10 dia- 

 meters. Locality: Devil's Bridge, Aberystwyth (coll. W. Keeping). 

 1 c, nat. size. • Loc. : Williamshope, Gala group (coll. C. Lapworth). 



2. Dictyonema delicatulum, sp. nov. : 2 a, nat. size ; 2 b, magnified 10 dia- 

 meters. Loc. : Bryn y Carnau (coll. W. Keeping). 



•3. Dictyonema corrugatellum, sp. nov. : 3 a, nat. size ; 3b, magnified 10 dia- 

 meters. Loc. : Devil's Bridge (coll. Dr. Humpidge, Aberystwyth). 



4. Ccdyptograptus plumosus, sp. nov. : nat. size. Loc. : Devil's Bridge 



(coll. W. Keeping). 



5. Acanthograptusramosus, sp. nov. : magnified 3 diameters. Loc: Devil's 



Bridge (coll. W. Keeping). 



6. CalyptograpUis digitatus, sp. nov. : 6 a, nat. size ; 6 b, magnified 5 dia- 



meters. Loc. : Devil's Bridge (coll. W. Keeping). 



7. Odontocaulis Kcepingii, gen. et sp. nov. : 7 a, nat. size ; 7 b, basal por- 



tion magnified 5 diameters. Loc. : Devil's Bridge (coll. W. Keeping). 



Discussion. 



The Peesident said that the paper was an important contribution 

 to the geology of Mid "Wales. The fossils were interesting and 

 remarkable, especially the Graptolites. 



Prof. Hughes pointed out that the North- Wales Silurian was 

 quite different from that of South Wales, and that the area described 

 by the author was far from the typical sections of either north or 

 south and differed from both. He considered the paper a valuable 

 contribution to our knowledge. 



Dr. Hicks was glad to hear that in this area also, as in Pembroke- 

 shire, there was no break between the Upper and Lower Silurians. 

 It was also satisfactory to see that fossils had turned up on 

 examination in these rocks, formerly reported to be barren or 

 nearly so. 



