33.47  The two slightly thicker horizontal lines divide the symbol into three main sections. The lowest of these sections symbolises the purely animal kingdom. This section is in turn divided into smaller, horizontal sections that are numbered nos. 21-24. These areas symbolise periods of evolution. Extending up through these sections in the symbol there are some vertical figures. These symbolise the various beings' mental impulses, thought climates or kinds of thoughts in the various periods of evolution. The figures are to be read from the bottom upwards. We see then their beginning, their growth towards their peak or the very height of their development and thereafter their degeneration or cessation, just as we can also see in the symbol which periods of evolution the figures or kinds of thoughts in question extend through.