Two species of _Pyrula_, viz.: _P. carica_ and _P. canaliculata_ were found, the first in considerable numbers. Neither of these species was found in any of the other heaps. Dr. Gould states that they are not known to exist north of Cape Cod. The largest specimen of the _P. carica_ was about seven inches in length, a portion of the spire having been broken off, and this, according to Dr. Gould, is their maximum size on the Coast of Massachusetts. It is, however, in remarkable contrast with a shell of the same species from one of the shell-heaps in Florida, which measured nearly fourteen inches in length. Of the remains of vertebrates, the bones of the deer were the most abundant; but those of the seal, the fox, the mink, of birds, including those of a duck and the wild turkey, of turtle and of fish were found. During a former examination of this locality by Mr. George G. Lowell and Dr. Algernon Coolidge, a canine of a bear and a part of the skull of a cat was obtained. No stone implements, but a few worked pieces of bone were dug up, and also some fragments from which portions had been sawed off. The tine of a deer’s antler, from which the tip had been sawed off, is represented on Pl. 15, fig. 14. About two-thirds of the metatarsal bone of the great toe from a human foot was found, in company with the bones of the animals already mentioned, and is the only portion of the skeleton of man which we have discovered while examining the heaps here described. The writer would express his obligations to Mr. George G. Lowell for the opportunity of examining the locality at Cotuit Port, and for the gift of valuable specimens. VII. _Age._ Shell-heaps have become intimately associated with the question of the age of the human race, a question which has passed out of the domain of the written, into that of geological history. It can only be satisfactorily answered by following the method of the geologist, when he attempts to determine the period when a given animal existed in former geological times, viz., by a careful comparison of the remains of such animal with those of existing species, and by an accurate study of the geological and other physical conditions under which they are found. In Denmark, such methods applied to the _Kjœkkenmœddings_, or refuse-heaps, have yielded results of great importance to archæology, and have shown that some of these heaps at least, as in Seeland along the Isefjord, date back to a period when their geological surroundings were somewhat different from what they now are, when the shores were less raised above the sea, and the oysters, of the shells of which the heaps are made up, had not yet retreated to where the fresher waters of the Baltic, at the present time, mingle with those of the ocean in the Kategatt.