On an aberrant Form of Truncatellina found in the Netherlands

From Mr. Ph. van Hooven I received a Truncatellina, found by himself on October 22nd, 1934, near Katwijk aan Zee (South Holland), at the foot of the downs. Judging by the soft parts, still present in the shell, this little snail must either have been collected in the living state or shortly after its death, as it was in fresh and uninjured condition. Probably the specimen was living in the downs and washed down by the showers or blown by the winds to the shore. It was already known that Truncatellina was an inhabitant of our downs, as a worn specimen of Tr. cylindrica (Fér.) in the "Genist des Hochofen-Stichkanales bei IJmuiden" (North Holland) was found by Mr. H. Steusloff in 1926, though till now this little snail has never been found again. The specimen collected at Katwijk (fig. 1) is of a cylindrical outline, with an obtuse apex and is slightly tapering towards the base. Whorls 6, including the 1 1/2 of the nepionic shell, which are smooth and sharply defined from the succeeding ones. The latter are convex and regularly rib-striate, the riblets numbering 3 to 0.1 mm on the last whorl. The aperture is ovate and the lip