KUNGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 48. N:o 1. 21 
Adeorbis S. Woop 1842. 
Whorls convex, the last large, obliquely flattened towards the aperture; umbilicus wide and deep, with 
an obtuse angular margin; colour reddish white. H. 1.7, D. 2 mm; Wh. 4 A. fragilis G. O. SaArRs 1878. 
Arehytrxa Costa 1869. 
Trachysma (JEFFrREYS M. 8.) G. O. SARS 1878. 
Whorls convex even at the aperture, not flattened below; umbilicus deep, moderately wide without 
angular border; colour transparent white. H. 1, D. 1.1 mm; Wh. 3!/2 (G. 0. SaArs) 
A. delicatum Pururpi 1844. 
Shell more dilated, base somewhat flattened, aperture oblique. H. 1.2, D. 1.4 mm 
var. expansa G. O. Sars 1878. 
