But, as you can see in Figures 43a, 44 to 50, those four birds can also be cut in four pieces in such a way that we can make eight fish (from the same Escher drawing 20) out of them! The trick here is to use combinations of tiling-lattices in different scales. We have seen this before in Figure 26.
Figure 43a
Figure 44
Figure 45
Figure 46
Figure 47
Figure 48
Figure 48a
Figure 49
Figure 50