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Show 678 REV. R. B. WATSON ON THE PECULIARITIES [Dec. 7, This genus thus bears to Achatina the same relation that Arion does to Limax, and Nanina to Helix. All the members of the genus have the shell highly polished, its brilliant lustre being obviously connected with the perpetual movement upon it of the mantle, and especially of its posterior prolongation, a movement also eminently characteristic of Nanina. In spite of very careful search no dart could be found. The jaw is horny, light brown, crescent-shaped, crossed from behind forwards by "numerous small converging ridges, one of which forms a distinct median line. The edge is not toothed, but forms a continuous curve. The radula consists of numerous rows of multitudinous teeth. The centre tooth is minute, with a sharp central point and a faint point on either side like a shoulder. It is attached to a strong, flat, basal plate, shaped like the crescent-formed cutting-knife of a shoemaker or half a dumb-bell. The lateral teeth are Fig. 1. Lovea (Achatina) tornatellina, Lowe. 1. enlarged; 1 a, natural size. 2. Jaw, greatly magnified. 3. Radula, central and first lateral teeth, magnified. 3. a, c, left and right laterals; ft, central tooth : greatly magnified. 4. Teeth intermediate between the centrals and extreme edge, greatly magnified. 5. Teeth at extreme edge, magnified; a, one of the same, greatly magnified. much larger, with a strongly developed centre point and two broad sharp shoulders. They are attached to flat, square, basal plates. As they pass over from the centre, they become more and more rudimentary (the outer shoulder first retreating toward the base), till they become at last mere square specks with an undefined back and a faintly serrated front edge. I believe that these features will be found common to all the distinctively Madeiran species of this group. Of course Achatina acicula and Cochlicopa lubrica (the maderensis |