What is a slender bony or cartilaginous process developed from the heel bone of bats. It helps to support the wing membranes. See Illust. of Cheiropter called?

heelspur — A slender bony or cartilaginous process developed from the heel bone of bats. It helps to support the wing membranes. See Illust. of Cheiropter. (Webster's 1913.)

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