Travel of the third category includes the work of the true wilderness explorers who add to our sum of geographical knowledge and of the scientific men who, following their several bents, also work in the untrodden wilds.  Colonel Rondon and his associates have done much in the geographical exploration of unknown country, and Cherrie and Miller have penetrated and lived for months and years in the wastes, on their own resources, as incidents to their mammalogical and ornithological work.  Professor Farrabee, the anthropologist, is a capital example of the man who does this hard and valuable type of work.

An immense amount of this true wilderness work, geographical and zoological, remains to be done in South America.  It can be accomplished with reasonable thoroughness only by the efforts of very many different workers, each in his own special field.  It is desirable that here and there a part of the work should be done in outline by such a geographic and zoological reconnaissance as ours; we would, for example, be very grateful for such work in portions of the interior of the Guianas, on the headwaters of the Xingu, and here and there along the eastern base of the Andes.

But as a rule the work must be specialized; and in its final shape it must be specialized everywhere.  The first geographical explorers of the untrodden wilderness, the first wanderers who penetrate the wastes where they are confronted with starvation, disease, and danger and death in every from, cannot take with them the elaborate equipment necessary in order to do the thorough scientific work demanded by modern scientific requirements.  This is true even of exploration done along the courses of unknown rivers; it is more true of the exploration, which must in South America become increasingly necessary, done across country, away from the rivers.

The scientific work proper of these early explorers must be of a somewhat preliminary nature; in other words the most difficult and therefore ordinarily the most important pieces of first-hand exploration are precisely those where the scientific work of the accompanying cartographer, geologist, botanist, and zoologist must be furthest removed from finality.  The zoologist who works to most advantage in the wilderness must take his time, and therefore he must normally follow in the footsteps of, and not accompany, the first explorers.  The man who wishes to do the best scientific work in the wilderness must not try to combine incompatible types of work nor to cover too much ground in too short a time.

There is no better example of the kind of zoologist who does first-class field-work in the wilderness than John D. Haseman, who spent from 1907 to 1910 in painstaking and thorough scientific investigation over a large extent of South American territory hitherto only partially known or quite unexplored.  Haseman’s primary object was to study the characteristics and distribution of South American fishes, but as a matter of fact he studied at first hand many other more or less kindred subjects, as may be seen in his remarks on the Indians and in his excellent pamphlet on “Some Factors of Geographical Distribution in South America.”