501. The succession of Churches in the course of time, and how, as is said, they were born one from another, resembles fruit or the seeds within fruit. in their centre or inmost parts there are, so to speak, the fruit of the fruit, or seeds of the seeds, from which there live so to speak in order the surrounding parts which develop at later stages. For the further those areas are from the middle towards the outermost parts the less are they essentially fruit or seed, until at length the skin or shell is reached where the fruit or seeds terminate. Or as with the brain, in the innermost areas there are delicate parts of its organic structure known as the cortical substances, from which and through which the soul functions. From these cortical substances finer coverings proceed in proper order, then those that are coarser. After that there are general coverings called meninges, and more general ones outside of these until the one on the very outside, which is the skull, is reached.