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HH25 | (4.5-5 days). Elbow and knee joints distinct. Digital plate in wing distinct, but no digits. Faint grooves demarcate the third toe on leg. Maxillary process lengthened, meeting wall of nasal groove (notice the notch at point of fusion). Three protuberances on each side of 1st visceral cleft. In dorsal view, 'a,' 'b,' and 'd' appear as round knobs, and 'c' as a flat ridge. Part 'f' ('collar') conspicuous and projects distinctly over the surface. Dorsal part of 3rd arch still visible. 3rd and 4th clefts reduced to small pits. |