S. hyattii new. Recessional after S. ci­neria-varia of Hog Island, but differs from it in a heavier, un sharpened margin, less well ­defined callus, more open aperture, larger ­parietal tooth, and more yellowish color to the fleckings. 600. Bar Bay Settlement, Current Island. This is an example of the far ­reaching effects of cyclic recession; not only does a watery space of some thirty miles in­tervene between the two species which show such close resemblances, but, as shown, each was derived from a separate fossil ancestor. I have named this exceedingly interesting species in honor of the late Professor Alpheus Hyatt who, when I first brought the series of shells, upon which I am now at work, from the Bahamas, went over them with me.

He was greatly impressed with the value of the series as illustrating the evolution of species and the ease with which species could be determined when com paired with others in mass. He also agreed with me in believing that a species may become established even though it is still bound to its parent species by living links, and counseled me never to abandon that idea.