138 Highbury Microscopical and Scientific Society. 



hard beds which mark the limits of the Middle Chalk was stated to 

 be very similar. 



In conclusion, the author considered that the divisions of the 

 Middle Chalk, as set forth in the Cambr. Memoir, are well shown 

 in the cliffs of Dover ; but the hard beds which appeared to him the 

 equivalent of the Chalk Rock, and mark the upper limit of Middle 

 Chalk, attaining a great development at Dover, it became necessary 

 to examine the palaeontological position of that bed to which the name 

 " Chalk Rock " was given by Mr. Whitaker. Having studied Mr. 

 Whitaker's description given in the "Geology of the London Basin," 

 and having examined exposures of this rock between Cambridge and 

 the Thames, he came to the conclusion that there was probably more 

 than one bed to which the name Chalk Rock might be applied, and 

 that these, probably not all persistent, may occur at different palason- 

 tological horizons. He therefore proposed to take the zone of 

 H. planus as the top of the Middle Chalk ; although this zone was 

 difficult to identify inland, from the paucity of its fossils, the base of 

 the overlying zone was well marked by the abundance of Micrastei-s 

 and other forms, which appear to him more closely allied to Upper 

 than to Lower Chalk. 



He believed that while the Chalk Rock seen at Henley may be 

 considered the summit of the Middle Chalk, the Chalk Rock of Cam- 

 bridgeshire, though convenient for marking the summit of the Middle 

 Chalk of that county, included that which was really the upper part 

 of the zone of H. planus and the base of the true Upper Chalk, the 

 equivalent of Chalk with many Micrasters of Dover. 



He would therefore consider the Middle Chalk of Dover to be that 

 included from the base of the grit-bed to the summit of the zone of 

 H. planus. Its thickness was 242 feet at Shakespeare's cliff. He was 

 indebted to M. Curry, Esq., of Dover, for this accurate measurement. 



IV. — Highbury Microscopical and Scientific Society. — At a 

 numerously attended meeting of the members of this Society, held 

 on Thursday, the 28th January, at Mr. E. P. Sell's, 63, Highbury 

 Hill, the President, James Smith, Esq., F.L.S., F.R.A.S., moved, 

 and Mr. Fitch seconded, the following resolution : — 



" That the Members of the Highbury Microscopical and 

 Scientific Society having heard with the most sincere regret 

 of the death of their Vice-President, Mr. J. B. Jeaffreson, 

 M.R.C.S., desire to place upon record their deep sense of the loss 

 they have sustained, and to express their appreciation and 

 admiration, not only of his attainments as a scientific man, and 

 the able manner in which he discharged the duties of Presi- 

 dent, but more especially of his character as a kind and 

 sympathetic friend ; and they furthermore desire that the 

 Secretary do, in a suitable manner, convey to Mi's. Jeaffreson 

 and the family the assurance of their heartfelt sympathy with 

 them in their sorrow." 



