238 Reports and Proceedings — 



Serw, the grit comes close upon Upper-Lingula flags. The division 

 of the Arenig volcanic rocks into Lower Ashes, Felstone, and Upper 

 Ashes, while true of some districts and useful as a generalization, 

 conveys an idea of uniformity of strata all round the anticlinal which 

 more detailed examination of different districts does not support. 



2. " The Tudor Specimen of Eozoon." By J. W. Gregory, Esq. 



After careful examination of all the slides and figures, and after 

 consideration of Sir W. Dawson's interpretation, the author is 

 absolutely unable to recognize in the specimen any trace of the 

 " proper wall," " canals," or " stolon passages " which are claimed 

 to occur in Eozoon, or any reasons for regarding the calcite bauds as 

 the " intermediate skeleton " of a Foraminifer. There are points in 

 Sir W. Dawson's figure which might pass as " stolon passages," but 

 they appear very different in a photograph, and the specimen agrees 

 with the latter. 



The author, however, gives reasons for concluding that the case 

 against the organic origin of the Tudor specimen does not rest on 

 negative evidence alone ; for though the rock is much contorted, the 

 twin lamellae and cleavage -planes of the calcite are not bent ; and 

 the fact that the crystalline bands cut across the bedding-planes 

 further shows their secondary origin. 



The rock in which the specimen was found is not " Lower 

 Laurentian," and is included by Messrs. Selwyn and Vennor in the 

 Huronian. 



IIL— March 25, 1891.— Dr. A. Geikie, F.R.S., President in the 

 Chair. — The following communications were read : — 



1. " Notes on Nautili and Ammonites." By S. S. Buckman, Esq. 



1. The Position of the Last Septum. — Mr. Bather's theory of shell- 

 growth in Cephalopoda (Ann. and Mag. Nat. Hist. 1888, p. 300) 

 seems to depend upon the idea that the last septum in the young in 

 Nautilus and Ammonites was alwaj^s formed at a proportionately 

 increased distance from the penultimate. This supposition is not 

 borne out by specimens of Nautilus, Witchellia , Lioceras, Ludwigia, 

 and Grammoceras examined by the author. 



2. Shell-muscles of Nautili and Ammonites. — Two specimens of 

 Ammonites in the author's collection are marked by impressions 

 which seem to indicate the position of the shell-muscle. 



2. " On the Drifts of Flamborough Head." By W. G. Lamplugh, 

 Esq., F.G.S. 



The author describes in detail the characters and distribution of 

 the glacial deposits on Flamborough Head, and classifies them as 

 follows : — 



Alluvial wash, freshwater marls, etc Eecent. 



Late glacial gravels ") 



Upper Boulder Clay | 



Intermediate Series. Stratified beds with bands of I ^, ■ ■, 



Boulder Clay \ ^l^"^^' 



Basement Boulder Clay ] 



Chalky rubble ; 



"Infra-glacial" beds of Sewerby and Speeton. 



