However, if this prohibition is formal in a large number of tribes[367]--with certain exceptions which will be mentioned later--it is incontestable that it tends to weaken as the old totemic organization is disturbed. But the restrictions which remain even then prove that these attenuations are not admitted without difficulty. For example, when it is permitted to eat the plant or animal that serves as totem, it is not possible to do so freely; only a little bit may be taken at a time. To go beyond this amount is a ritual fault that has grave consequences.[368] Elsewhere, the prohibition remains intact for the parts that are regarded as the most precious, that is to say, as the most sacred; for example, the eggs or the fat.[369] In still other parts, consumption is not allowed except when the animal in question has not yet reached full maturity.[370] In this case, they undoubtedly think that its sacred character is not yet complete. So the barrier which isolates and protects the totemic being yields but slowly and with active resistance, which bears witness to what it must have been at first. It is true that according to Spencer and Gillen these restrictions are not the remnants of what was once a rigorous prohibition now losing hold, but the beginnings of an interdiction which is only commencing to establish itself. These writers hold[371] that at first there was a complete liberty of consumption and that the limitations which were presently brought are relatively recent. They think they find the proof of their theory in the two following facts. In the first place, as we just said, there are solemn occasions when the members of the clan or their chief not only may, but must eat the totemic animal or plant. Moreover, the myths relate that the great ancestors, the founders of the clans, ate their totems regularly: now, it is said, these stories cannot be understood except as an echo of a time when the present prohibitions did not exist.