

THE 



QUARTERLY JOURNAL 



GEOLOGICAL SOCIETY OF LONDON. 



EDITED BY 



THE ASSISTAJSTT-SECEETAEY OE THE GEOLOGICAL SOCIETr. 



Quod 3i cui mortalium cordi et curse sit non tantum inventis haerere, atque iis uti, sed ad ulteriora 

 penetrare ; atque non disputando adversarium, sed opere naturam vincere ; denique non belle et probabiliter 

 opinari, sed certo et ostensive scire ; tales, tanquam veri scientiarum filii, nobis (si videbitur) se adjungant. 

 —Novum Organum, Prafatio. 





VOLUME THE FORTY-FIRS 



1885e ..: 



LONDON: 



LONGMANS, GEEEN, AND CO. 



PARIS: FRIED. KLINCKSIECK, 11 RUE DE LILLE; F. SAVY, 24 RUE HAUTEFEUILLE 

 LEIPZIG: T. O.WEIGEL. 



SOLD ALSO AT THE APARTMENTS OF THE SOCIETY, 



MDCCCLXXXV. 



