Figure 5 in Comparative morphology of the finlet spines of the extant Polypteridae (Osteichthyes; Cladistia). Systematic interest

Figure 5. – Schematic drawing showing the seven stages (from the left to the right: A-G), of the formation of the finlet spine (B-G) at the surface of the lepidotrichium (A), and of three different secondary branches (1, 2, 3) (C-G) of the finlet lepidotrichium. The spine grows in length towards the tip of the finlet, and so progressively includes the primary lepidotrichium (C-G).