Crossword-Solution: TETRAPODS 9 letters, 2 clues 🏆 scrabble score: 12

The most striking feature of the humerus is a slender hooklike process on the posterior edge near the distal end, probably homologous with (1) the posterior flange on the "humerus" in Rhipidistia, and (2) the entepicondyle of the humerus in _Archeria_ (Romer, 1957) and other tetrapods.

More notable are the views of several Scandinavian workers (Säve-Söderbergh, 1934; Jarvik, 1942; Holmgren, 1933, 1939, 1949a, b), of whom Jarvik, in a thorough analysis of the ethmoid region, would derive the Urodela from Porolepid Crossopterygii, and all other tetrapods from the Rhipidistia; Säve-Söderbergh and Holmgren, the latter using the structure of carpus and tarsus, see a relationship of Urodela to Dipnoi, but accept the derivation of labyrinthodonts and other tetrapods from Rhipidistia.

For instance Holmgren's numerous figures of embryonic limbs of salamanders show patterns of cartilage elements that he would trace to the Dipnoan type of fin, yet it is difficult to see that the weight of evidence requires this, when the pattern does not differ in any fundamental manner from those seen in other embryonic tetrapods, and the differences that do appear may well be taken to have ontogenetic rather than phylogenetic meaning.