Vlll INTRODUCTION. 



Ferussacidae (Vol. XVIII, p. 211; this volume, p. 1). Hoi- 

 arctic, Oriental, African, Neotropical. 



Amastridoa (Vol. XXI). Hawaiian Is.; Juan Fernandez. 

 Achatinellidse (Vol. XXI). Hawaiian Islands. 

 Tornatellinidse (Vol. XXII) . Pacific Islands. 



