Japanese Land-Snails. 3 
Shikoku, and Kiushiu remained connected until very recent 
time, and have been separated within the life of those slightly 
differentiated races which we term ‘ subspecies.” From 
southern Kii, through Awaji and Shikoku Islands, across 
Bungo Channel to Kiushiu, and westward across the lower 
end of the Inland Sea to the west end of Hondo, must have 
been a continuous land-area since Pliocene and down to 
geologically recent time. Not only numerous species, but 
mere races of more widely spread species, occupy this area, 
and such a distribution is quite inexplicable except upon the 
theory that the areas in question, though now separated, were 
until recently a unit geographically, as they still are faunally. 
There are doubtless species existing on Shikoku Island which 
do not extend beyond its limits; but the local differentiation 
is not greater than upon an equal area of Hondo and does 
not make against the view just set forth. 
In respect to classification and generic nomenclature, the 
Japanese Zonitide are in great confusion. Reinhardt, many 
years ago, referred the species known to him to European 
groups of the family. arly last year I recognized the fact 
that the Japanese Zonitide belong mainly to Oriental, not 
European genera. This opinion found expression in articles 
published in August (vr. p. 882) and November (xv. p. 81), 
in which I referred various species to the Oriental genera 
Macrochlamys and Kaliella, showed that the name Luconulus, 
Reinh., must replace the names Conulus and Arnouldia, and 
expressed my belief that the Japanese species referred to 
these groups really belong to Kaliella. Dr. v. Méllendorff, 
in an article just published (XxI. pp. 35, 37), has reached 
conclusions in part anticipated by my papers, in part at 
variance with them. He has referred numerous species to 
the genus Microcystina of Mérch, most_of them, I think, 
incorrectly. The establishment of Mvcrocystina upon an 
adequate basis we owe to Godwin-Austen, who showed that 
it is characterized by a callous thickening or flexure of the 
columella. Of the Japanese species known to me by speci- 
mens, only Arnouldia ceratodes, Gude, has this feature. J 
consider v. Mollendorff’s reference of this species to Micro- 
cystina justified. The species Denitzi, sinapidium, and 
Hirasei of his Microcystina list have the shell-characters of 
Macrochlamys, and not of Microcystina. Most of the other 
species he mentions are known to me, as they are to him, by 
the descriptions only, and their generic reference is little 
better than guesswork. 
Gastrodontella, Méllendorff, a new genus proposed for 
G. japonica, Mildff. (1901), a synonym of Kaliella multi- 
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