ABSTRACT
Cecal Appendix, "announced" in Reptiles and anatomically established as a lymphoid organ in Birds, in Mammals first contribute to the passage from Prototheria (oviparous) to the Eutheria (viviparous), than it permits, through the setting of Congenital Inherited Tolerance, the appearance and survival of a new Order: Primates.

In Man, the Cecal Appendix has a peculiar function: it is the lymphoid organ that as the physiological role of permitting the procreation and preservation of the Species.