Fig. 904.
Alaria (Anchura) carinata Mant. Gault, Folkestone.
Fig. 905.
Spinigera semicarinata Goldf. sp. Callovien. Montreuil-Bellay, Maine et Loire.
Subgenera: Alipes Conrad, Arrhoges Gabb., Ceratosiphon Gill, Cuphosolenus Piette, Tessarolax Gabb., Lispodesthes White (Fig. [907]), Helicaulax Gabb., Dimorphosoma St. Gardner (Fig. [908]), Pterocerella Meek, Malaptera Piette. Jura. Kreide.