Figure 8 in REVIEW Vertebrate origins are informed by larval lampreys (ammocoetes): a response to Miyashita et al., 2021

Figure 8. Pharynxes of lampreys and a jawed shark, compared. Frontal sections. A, ammocoete; B, adult lamprey; C, shark; D, an enlarged gill of each. The similarities are emphasized by colour-coding. The blue arrows in (A–C) show the direction of flow of the ventilatory water. In (A) the green skeletal arches are made of mucocartilage and the purple arches consist of typical, cellular cartilage (hyaline). The extrabranchial cartilages of sharks are comparable to the external branchial arches of lampreys. (A) is redrawn from Mallatt & Ridgway (1984), (B) from various sources including Randall (1972), (C) from Mallatt (1997/98) and (D) from Mallatt (1996).