This group comprises the largest and most familiar garden snails of Japan, distributed from southern Hokkaido to Yakushima and Tanegashima, south of Kyushu. The shells have a rather low spire containing about 6 whorls, which gradually increase their width toward the aperture. The aperture is rather wide and slightly oblique downwards, and its margin is thickened and reflexed in adult shells. The umbilicus is narrowly but deeply perforated. The animals have a dart sac with mucus glands, and the penis is attached with a flagellum and without an appendix. These are the characteristic features of this group to separate it from the superficially allied Satsuma-group belonging to Camaenidae.
Four spiral color bands on the surface of body whorl are also characteristic of this genus, and are variously combined into several kinds of common design. The bands in full set consist of the subsutural, (1), peripheral (2) and basal (3) bands and the umbilical patch (4). This design is called the sandai-pattern. The subsutural band frequently drops, resulting in the callizona-pattern. When the subsutural and basal bands are both lacking, the design is called the eoa-pattern. Another common design is the herklotsi-pattern, in which the subsutural and basal bands are wide and fading toward the suture and the umbilicus respectively. There also is the bandless form, and there is the nimbosa-pattern consisting of oblique, golden yellow streaks. The last pattern may be superposed upon any other patterns. Other patterns than these are rather exceptional. A single population of the same species usually includes a few or more of these different combinations of color bands.
Certain species of this genus as E. callizona, E. congenita, E. dixoni, etc. are mainly arboreal in their life, and have thin, whitish shells, while others are terrestrial, having thick and dark-colored shells, as in E. sandai, E. eoa, E. senckenbergiana, etc. Species of the latter group generally include two races which are connected by various transitional forms. One is the hill race that has larger, dark brown-colored shell, and contains many-banded individuals in high percentages. Another is the lowland race that has smaller, light-colored shells, especially rich in eoa-patterns. The two races of the same species are so widely different in appearance that the identification of species is sometimes extremely difficult without the anatomical examination of genital organs.