and night is, in some cases, explained as due to the original theft of daylight by a culture hero, who, finding himself closely pursued, casts out the daylight bit by bit. Again, the markings in the bark of the birch trees are explained on the ground that once a culture hero in anger gashed the tree with his knife. Yet, if we take native myths as they come, such explanations much more often apply to peculiarities of the heavens and the markings upon birds and animals than to other classes of phenomena. Another peculiarity is that the initial creation of the world is a single incident, generally disposed of in a single simple narrative, whereas we find many complex independent tales, each accounting for more or less trivial animal markings. Waterman[1] has discussed this diffuse explanatory character of American tales under the designation, explanatory element. The important problem is as to whether these tales were originally composed as theoretical explanations of natural phenomena in each case, or whether the explanatory applications were mere afterthoughts. Waterman's investigation, in particular, seems to make it clear that in the New World such explanations are quite secondary and could not have been in the mind of the first composer. This conclusion is reached by a comparative study of the myths for many tribes and is, of course, inferential.
The place of the heavenly bodies in aboriginal myth has been investigated by Ehrenreich,[2] who defended a theory which states that most of the plots in all tales were but variations of a single theme in which the sun and moon were the leading characters. He took as one of his main factors the submitting of a hero to various kinds of tests. This topic also has been made the subject of exhaustive inquiry under the title of The Test Theme.[3] Here, again, the result is negative, and Ehrenreich's theory has been retired to the historical cabinet.
While such problems are of great interest, their solutions are contingent upon facts of distribution. The data so far accumulated enable us to compare the mythologies of the several tribes occupying large areas. When we do so, we find
