﻿226 Revieics — The PalceontograpMcal Society. 



1. Dr. Wright gives part 6tli of vol. i. of the Cretaceous Echino- 

 derms, especially of the genera Cottaldia, Discoidea, and Ecliinocomis. 

 In treating of the " Echinoidea exocyclica," the author takes great 

 care to define the seven groups in which Breynius, one of the first 

 and best of early Echinodermatologists, arranged the Echinidae, with 

 the synonyms used by others ; and he gives a translation of the 

 rare " Schediasma de Echinis," etc., from Breynius's " Dissertatio 

 physica," etc., 1732. 



2. Mr. Davidson adds to his immense collection of Brachiopodal 

 literature and iconography some valuable supplemental notes, de- 

 scriptions, and figures of Tertiary and Cretaceous species, either new 

 or not sufficiently well known. 



This enthusiastic student of Brachiopodal life-forms, having him- 

 self drawn on stone for the Society upwards of 200 quarto plates, 

 often crowded with good figures, has thus enabled the Society to 

 expend considerable sums on the illustration of other subjects, 

 which would else have waited, perhaps in vain, for costly figuring. 



3. Mr. S. V. Wood, the veteran geologist of the Crag, contributes 

 a Supplement to his monographic account of the Bivalves of the 

 Crag (and this Supplement is a monograph of itself, with 5 plates), 

 some concluding remarks on the distribution of the Crag fauna, and 

 an admirable " Synoptical List of Marine Mollusca from the Upper 

 Tertiaries of the East of England," with remarks and an analysis of 

 the list. The stratal grouping adopted ' is (downwards) : 



Post-Glacial ; Valley Gravel, and Upland and Lowland 

 Brick-earths. 



Plateau 1 p^gt. Glacial, and Glacial (?). 



Gravel. ) 



Upper Glacial ; the great Chalky Boulder-clay. n 



Middle Glacial ; Sand and Gravel. f Glacial 



T r^i • 1 ( Ilie Contorted Drift. ( Beds. 



Lower Glacial | rpj^^ p^^^^j^ ^^^^ ^^^ Pebble-beds. ) 



Chillesford Beds ; Clay and Sand. \ 



Fluvio-marine Beds. ^ 



T) n ( Bed Crag, excepting the Scrobicularia-beds above, and i- ^VV^^ 

 ^^^ the Walton Crag below. ^^^S- 



^^^S- { Older or Walton Bed Crag. j 



Coralline Crag. j ^°rn°' 



° I White Crag. 



" The results of the Table indicate," writes the author, p. 220, "an almost identical 



per-centage of forms not known as living in the case of the older Red Crag and the 



Coralline, which is in conflict with the geological break, which I still believe to exist 



between the two formations. With the exception of the Middle Glacial column of it, 



however, the Table shows very forcibly the diminishing Mediterranean aspect of the 



fauna as we ascend in the geological scale. In the Coralline Crag there are fifty-two 



Mediterranean forms not living in the British seas, and only twenty of the converse 



character ; and of these twenty, two, viz. Odostomia Gulsonce and Psammobia 



tellinella, are Lusitanian. In the Walton Bed Crag the respective numbers are 



fourteen and thirteen ; but in the rest of the Red Crag the British species not living 



in the Mediteranean are in number more than double those of the converse character; 



while in the Fluvio-marine Crag these proportions are increased five-fold; and in 



the Chillesford beds nineteen-fold. In the Lower Glacial there occur thirteen, in 



the Upper Glacial twenty-one, and in the Post-Glacial nineteen British species un- 



1 See also the Introduction to this Supplement, Part 1, 1872, by S. V. Wood, Jun., 

 F.G.S., and F. W. Harmer, F.G.S. 



