266 Notices of Memoirs — Mr. J. H. Blake's Address — 



7. Zone of Cyclognathus micropygus, Linnrs. 



6. ,, Peltura scaraheoides, "Wahl. 



5. ,, Leptoplastus stenotus. 



4. ,, Farabolina spinulosa, Wahl. 



3. „ Beyrichia Angelini^ Barr. 



2. ,, Olenus truncatus, Bronn. 



1. ,, Olenus gibbosus, Wahl. 



(1, 2). In the typical section of Andrarum, the basal zones 1 and 

 2 appear to be only dubiously separable, judging from the carefully 

 prepared section and tables of Dr. TuUberg.' They are unitedly 

 about twenty feet in thickness, and contain throughout the well- 

 known Agnostiis pisiformis of Linneeus. The included species of 

 Olenus (0. truncatus, Bronn, and 0. gibhosus, Wahl., 0. attenuatus) 

 appear to occur together in the central horizons. (3.) The succeeding 

 five feet of shale, with Beyrichia Angelini, Barr., Agnostus cyclopyge, 

 Tullb., and forms of Olenus and Ceratopyge, may be assigned to the 

 third zone. (4.) The fourth zone, distinguished by the possession 

 of the remarkable ParaboUna spinulosa, Wahl., is about ten feet in 

 vertical extent. (5.) Zone 5 is about the same thickness, and is 

 individualized by the presence of Leptoplastus oratus, L. stenotus, 

 Etirycare angustatum, Ang., E. camuricorne, Aug., and a form of 

 Sphmrophthalmus. (6.) Zone 6 is one of the best-marked zones in the 

 series. It appears to be about twelve feet in thickness, and is 

 characterized by Peltura scaraheoides, Agnostus trisectus, Salt., 

 Ctenopyge pecten, Salt., sp., Ctenopyge bisulcata, Phill., sp., etc. (The 

 fossils of this zone have been recently described by Linnarsson in a 

 valuable memoir that will be noticed later on.) (7.) Finally, we 

 have a terminal zone about eight feet in thickness, containing 

 Cyclognathus micropygus, Linn., and forms of Acei'ocare and Orthis. 

 {To be continued in our next Number.) 



^^OTiciES OIF iMiiEjnycoiias. 



I. — Address on the Age and Eelation of the so-called "Forest- 

 bed " OF THE Norfolk and Suffolk Coast.^ 

 By J. H. Blake, Assoc.M.Inst.C.E., F.G.S. ; 

 of H.M. Geological Survey of England and Wales ; 

 President of the Norwich Geological Society. 



AFTEE referring to the many conflicting opinions expressed on 

 the subject, Mr. Blake called attention to his paper " On the 

 Age of the Mammalian Eootlet-bed at Kessingland," and continued 

 as follows : — I stated it marked an horizon of considerable importance 

 with respect to the correlation of the beds in Norfolk and Suffolk, and 

 occurred at the upper part, or thereabouts, of what is generally known 

 as the Cromer Pre-glacial Forest-bed Series, and beneath the Lower 

 Glacial Series of Messrs. Wood and Harmer.^ This line is a line of 

 denudation, and indicates in places a true land- surface, proved by 

 rootlets in situ, observed by myself at the extreme ends and in 



^ Tullberg, Agnostus-Arterna vid Andrarum, pp. 8, 9, etc. 



- Abridged from the Proceedings of the Norwich Geological Soc, vol. i. pp. 137-160. 



3 Geol. Mag. Dec. II. Vol. IV. p. 299. 



