Figure 4 in The trouble with flippers: a report on the prevalence of digital anomalies in Cetacea

Figure 4. Tracing (A) and radiograph (B) of the right flipper of a grey whale (Eschrichtius robustus, LACM 54543). An additional digit lies between digits IV and V, and is represented by a single rounded metacarpal and three phalanges. The dotted line indicates the extent of cartilage shared between digit IV and the anomalous digit. Tracing (C) and radiograph (D) of the flipper of a fin whale (Balaenoptera physalus, USNM 550116). Three additional phalanges are embedded in the connective tissue between digits IV and V. Scale bars: 1 cm. Key: metacarpals, dark grey; phalanges, light grey; cartilages, white; anomalous elements, black.