also resemble the reindeer of Siberia. It is, therefore, not an improbable conjecture that there were two migrations into America, one of the barren-ground type from western Europe, by way of the Spitzbergen land connection, and the other of the woodland, from Siberia, by way of Alaska. Little more can be said, perhaps even less, of the other circumpolar genus, _Alces_, known in America as "moose," and across the Atlantic as "elk." It also is of mixed character in relation to the two great divisions we have had in mind, but in a different way from reindeer. Like American deer it has the lower ends of the lateral metacarpals remaining, and the antlers are without a brow-tine, but like _Cervus_ it has an incomplete vomer, and unlike deer in general, the antlers are set laterally on the frontal bone, instead of more or less vertically, and the nasal bones are excessively short. The animal of northern Europe and Asia is usually considered to be distinct from the American, and lately the Alaskan moose has been christened _Alces gigas_, marked by greater size, relatively more massive skull, and huge antlers. Of the antecedents of _Alces_, as in the case of the reindeer, we are ignorant. The earlier Pleistocene of Europe has yielded nearly related fossils,[2] and a peculiar and probably rather later form comes from New Jersey and Kentucky. This last in some respects suggests a resemblance to the wapiti, but it is unlikely that the similarity is more than superficial, and as moose not distinguishable from the existing species are found in the same formation, it is improbable that _Cervalces_ bore to _AIces_ anything more than a collateral relationship. [Footnote 2: The huge fossil known as "Irish elk" is really a fallow deer and in no way nearly related to the moose.] Even to an uncritical eye, the differences between ungulates and carnivores of to-day are many and obvious, but as we trace them back into the past we follow on converging lines, and in our search for the prototypes of the carnivora we are led to the _Creodonta_, contemporary with _Condylarthra_, which we have seen giving origin to hoofed beasts, but outlasting them into the succeeding age. These two groups of generalized mammals approached each other so nearly in structure, that it is even doubtful to which of them certain outlying fossils should be referred, and the assumption is quite justified that they had a common ancestor in the preceding period, of which no record is yet known.