Note 100 — Section F.

I am indebted to M. Bosquet for a specimen, bearing this name and reference, found in the ‘Systeme Bolderien’ of Dumont, (miocene according to Sir C. Lyell) at Bolderberg. The specimen consists of a rostrum, with a portion of the base attached; and as these parts are in some degree characteristic, I fully believe this specimen to be the B. bisulcatus. I hope hereafter to give in the Palæontographical Series fuller illustrations of this and the following fossil species.