This fluctuating character of the nomenclature explains the instability of the names of the months; when anything new happens which is of importance for the life of the people, it serves to describe a month. Thus the Lenope, after they migrated inland, where no shads were found, renamed the shad-month the sugar-refining month[818]; and the Pima, after they had learnt to cultivate wheat, named a month from the wheat harvest[819]. The best evidence is the multiplicity and diversity of the names of months, which is found everywhere, even among the most closely related peoples and tribes, or different groups of the same tribe, as is shewn by the above series of months from beginning to end. Most significant and by no means isolated is the case of the Cheyenne, different groups of whom have separate names for the months. Since they are well acquainted with the customs of the animals and roam over wide areas, they easily recognise any name for a month, even if they themselves do not use it. The reason for this is also that the seasons, which serve as descriptions of the months, are common to all and at once become intelligible[820]. They have not been fixed in a conventional series, as is the case with the months as we conceive them; ours is the final point of the development, which begins with a chaotic mass of names of months. We see that at this stage the number of months is indifferent: the question how many months the year has simply does not exist, and consequently there is no need to make the series of moon-months fit into the solar year. There are peoples who do not even extend the reckoning by moons to the whole year. There is a time ‘in which nothing happens’, which is quite without interest and in which no one takes the trouble to observe or name the moons. Such a period is e. g. the depth of winter in the far north, when people only vegetate, as well as they can. Among the tribes of the Kamchatka river the tenth and last month is said to be as long as three others[821]. The Amansi, one of the Ibo-speaking tribes, reckon ten months and an _evulevu_ (idiot, nothing, empty month)[822]. More often we find series of months with less than twelve names. The inhabitants of the Marquesas Islands had a ten-month year, although as well as this they knew the complete year, which was reckoned and named according to the Pleiades[823]. Even the Maoris are said to have counted no more months after the tenth[824]. The Yurak Samoyedes and the Tunguses of the Amur count only eleven months, the northern Kamchadales ten[825]. The Yeneseisk Ostiaks name only the months of one half of the year, the seven winter months[826], and so do many Indian tribes. The Bannock have no names for the months of the warm season of the year[827]. Many Cheyenne tribes have only six months with names[828]; the present condition of the calendar of the Hopi and Zuñi points to the fact that this was really the case with these tribes also[829]. The Diegueño of S.