42 Reports and Proceedings — 



volved in their first appearance after the genera which they might, 

 otherwise, he supposed to connect. 



The author is also of opinion, that the simultaneous occurrence 

 of twelve primitive, cosmopolitan types at the base of the second 

 Silurian zone (=L.S.) is absolute proof of their independent origin. 

 It must, however, be noted that the assumed absence of all Cepha- 

 lopods and Acephala in the primiordial zone rests solely on 

 negative evidence, and testimony of that nature is subject to con- 

 tinual modification, of which the long controverted existence of 

 fishes in the Upper Silurian rocks and of Mammalia in the Pur- 

 becks may serve as examples. It is probable, also, that Evolutionists 

 will be inclined to regard the wide distribution of the so-termed 

 primitive types as indicating their antiquity, and they will not, 

 therefore, share M. Barrande's ideas as to the utter impossibility of 

 the discovery of a centre of development in some of the unexplored 

 Cambrian areas. It may be added that in the Lower Tremadoc 

 rocks of St. Davids, in South Wales (now classed on pal^onto- 

 logical grounds as Upper Cambrian), Mr. Henry Hicks has already 

 recorded the presence of one species of OrtJioceras and twelve of 

 LamelUbrancJiiata. 



In concluding his investigations M. Barrande alludes in eulogistic 

 terms to the admirable memoir by Mr. Thomas Davidson ' on 

 " What is a Brachiopod ? " He refers, likewise, to the publications 

 of M. Grand'Eury on the Carboniferous flora of Central France, 

 and to the views expressed by Mr. Carruthers in his address to the 

 Geologists' Association,^ as being in complete accordance with the 

 results of his own researches, and thus considers it manifest that no 

 support to the theory of Evolution can be derived either from the 

 Vegetable Kingdom, or from the Brachiopoda, Crustacea, and Cepha- 

 lopoda in the animal domain. 



The foregoing Table (pp. 40-41), compiled from five of the author's, 

 indicates the chief points of his classification, the geological, and 

 geographical horizons of the primitive types, the vertical distribution 

 of the families Nautilidm, Ascoceratidce, and Goniatidcs, and the number 

 of species of each genus in which the embryological characters have 

 been satisfactorily determined.^ A.C. 



■i^iBiPOieTs j^isTJD :E5E,oG:EEX)in^a-s. 



Geological Society of London. — I. — Nov. 21, 1877. — John Evans, 

 Esq., F.E.S., D.C.L., Vice-President, in the Chair.— The following 

 communications were read : — 



1. " On the Glacial Deposits of West Cheshire, together with Lists 

 of the Fauna found in the Drift of Cheshire and adjoining Counties." 

 By W. Shone, Esq., F.G.S. 



The conclusions arrived at by the author in this paper were as 



1 Geol. Mag., April, May, June, 1877. » Geol. Mag., Dec. 1876. 



^ For a previous reyiew of M. Barrande's laboui's on Cephalopoda, see Geol. 

 Mag. 1870, Vol. VII. p. 486. 



