234 Reports and Proceedings — Geological Society of London. 



smaller spherulitic structure was set up in the large spherules after 

 their formation. In the present paper evidence was adduced in 

 favour of a different mode of origin. It was argued that the small 

 spberulitic bodies (primitive spherulites) were developed in the 

 obsidian before it assumed a condition of rigidity, and that they 

 floated towards certain points in the still viscid lava, and segregated 

 in more or less spherical groups, though there is no evidence to show 

 what determined their movements ; furthermore, that from a point 

 or points situated at or near the centre of each group, crystallization 

 was set up, giving rise to a radiating fibrous structure, which 

 gradually developed zone after zone of divergent fibres until the 

 entire mass of primitive spherulites was permeated by this secondary 

 structure — a structure engendering a molecular rearrangement of 

 the mass, such as would obliterate any trace of structure which the 

 primitive spherulites might have originally possessed. 



In a supplementary note the views of Mr. J. P. Idclings with 

 reference to the spherulites in question were given. Mr. Iddings 

 considers that the structures here described as primary are of second- 

 ary origin. The author stated in detail his reasons for adhering to 

 the conclusions given in this paper. 



3. "A Monograph of the Bryozoa (Polyzoa) of the Hunstanton 

 Eed Chalk." By George Bobert Vine, Esq. Communicated by 

 Prof. P. Martin Duncan, F.B.S., F.G.S. 



The fossils examined occurred on tests of Echinoderms and on 

 the shells of Terebratula hiplicaia, T. capillata, Oysters, Inoceranri, 

 Nautili, and Ammonites-. The best of the forms of Diastopora and 

 Proboscina are found on Tuocerami and Ammonites, but the most 

 abundant individuals are Stomatoporce, chiefly on Terebratula bipli- 

 cata. Species of Entalophora, Idmonea, and " Ceriopora " are very 

 rare or badly preserved, and Cbilostomatous forms are also very rare. 



In the present monograph the author felt obliged to limit or 

 re-define the generic terms employed, and proceeded to describe in 

 detail the forms which he has examined from the Hunstanton Bed 

 Chalk and other Cretaceous deposits, including the following new 

 forms : — Proboscina irregularis, P. uberta, P. gracilis ?, var. Reussi, 

 P. claviformis, P. hunstantonensis, and var. ampliata, P. Jessoni, 

 P. gigantopora, P. dilatata, var. cantabrigiensis, Diastopora hunstan- 

 toueutis, D. foecunda, D. Jessoni, and Membranipora gaultina. 



4. Evidence furnished by the Quaternary Glacial Epoch Morainic 

 Deposits of Pennsylvania, U.S.A., for a similar mode of formation of 

 the Permian Breccias of Leicestershire and South Derbyshire." By 

 William S. Gresley, Esq., F.G.S. 



The author noted that nodules of ironstone occurring in the Penn- 

 sylvanian glacial deposits of Quaternary age are scratched in 

 precisely the same manner as those which he has described from the 

 Permian deposits of Leicestershire and Derbyshire, and concluded 

 that one and the same agency, viz. ice, has been instrumental in 

 producing the observed results in both cases. 



