FIG. 7. The modes of development of barb ridges in culture. A . A "ventral
triangle" shown in negative; this shows the form of the barbs rather better in this
specimen, which is the most perfect yet attained. It is from a Light Sussex neck
feather collar, mid ventral. A few "mistakes" are apparent, but the pattern of barbridge formation is definitely that characteristic of the most ventral generator. The
white fiVki are mostly melanocytes.
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