Page:Land Mollusca of North America (north of Mexico) Vol. I Part 1 i-276.pdf/5

• New Families, Subfamilies, Genera and Subgenera Defined in Volume I
• New Species, Subspecies and Formae Defined in Volume I, Part 1
• INTRODUCTION: Measurements and Colors — Illustrations — Types — References — Stages of growth — Species and Subspecies — Genera — Synoptic Key to new Genera of Part II
• SYSTEMATIC TREATMENT

• Family I. Helicidae

• Genus Helix

• Subgenus Helix, s.s.
• Subgenus Cryptomphalus

• Genus Cepaea
• Genus Otala
• Genus Helicigona
• Genus Theba

• Family II. Helicellidae

• Genus Hygromia

• Subgenus Trichia

• Genus Monacha
• Genus Helicella

• Subgenus Trochoidea

• Genus Cochlicella

• Family III. Helminthoglyptidae

• SUBFAMILIY CEPOLIINAE

• Genus Cepolis

• Subgenus Hemitrochus

• SUBFAMILIY HELMINTHOGLYPTINAE

• Genus Monadenia
• Genus Helminthoglypta

• Subgenus Helminthoglypta s.s.
• Subgenus Charodotes

• Genus Micrarionta

• Subgenus Micrarionta s.s.
• Subgenus Eremarionta
• Subgenus Xerarionta
• Subgenus Plesarionta

• SUBFAMILIY SONORELLINAE

• Genus Sonorella

• Subgenus Sonorella s.s.