Those holding the opinion that the Indians were not the authors of these works, although agreeing as to this point and hence included in one class, differ widely among themselves as to the people to whom they are to be ascribed, one section, of which, as we have seen, Dr. Harris may be considered the pioneer, holding that they were built by the Toltecs, who, as they supposed, occupied the Mississippi Valley previous to their appearance in the vale of Anahuac. Among the more recent advocates of this theory are Mr. John T. Short, author of "The North Americans of Antiquity;"[47] Dr. Dawson, in his "Fossil Man," who accepts the tradition respecting the Tallegwi, but identifies them with the Toltecs; Rev. J. P. MacLean, author of the "Mound Builders" and Dr. Joseph Jones, in his "Antiquities of Tennessee." Wilson, in his "Prehistoric Man,"[48] modifies this view somewhat, looking to the region south of Mexico for the original home of the Toltecs, and deriving the Aztecs from the mound-builders. Another section of this class includes those who, although rejecting the idea of an Indian origin, are satisfied with simply designating the authors of these works a "lost race," without following the inquiry into the more uncertain field of racial, national, or ethnical relations. To this type belong a large portion of the recent authors of short articles and brief reports on American archæology, and quite a number of diligent workers in this field whose names are not before the world as authors. Baldwin believes that the mound-builders were Toltecs, but thinks they came originally from Mexico or farther south, and, occupying the Ohio Valley and the Gulf States, probably for centuries, were at the last driven southward by an influx of barbarous hordes from the more northern regions, and appeared again in Mexico.[49] Bradford, thirty years previous to this, had suggested Mexico as their original home.[50] Lewis H. Morgan, on the other hand, supposes that the authors of these remains came from the Pueblo tribes of New Mexico. Dr. Foster[51] agrees substantially with Baldwin. We might include in this class a number of extravagant hypotheses, such as those held by Haywood, Rafinesque, and others among the older, as well as by a few of the more recent authors. The opposite class, holding that the mound-builders were the ancestors of some one or more of the modern tribes of Indians, or of those found inhabiting the country at the time of its discovery, numbers comparatively few leading authorities among its advocates; in other words, the followers of Bishop Madison are far less numerous than the followers of Dr. Harris. The differences between the advocates of this view are of minor importance, and only appear when the investigation is carried one step further back and the attempt is made to designate the particular tribe, nation, people, or ethnic family to which they appertained.