Following up the notes which recently appeared on Cretaceous Aporrhaïdæ, I now propose to continue from time to time notes on other Cretaceous Gasteropoda. At present I have selected for illustration “Scalariform Shells.” The most recent papers which refer to this subject are witnesses how much revision of the genera and species is needed to which our British Cretaceous representatives of this type have been assigned. I first take the family of Scalidæ, and will, as briefly as possible, endeavour to recapitulate what is at present known of this family.