Page:Darwin - The various contrivances by which orchids are fertilized by insects (1877).djvu/256

236 so many groups of spiral vessels, in every case traced down to one of the six large ovarian groups. They alternate in five whorls, as represented; but I have not attempted to give the actual distances at which they stand apart. In order to guide the eye, the three central groups running to the three pistils are connected by a triangle.

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The little circles show the position of the spiral vessels.

Five groups of vessels run into the three sepals together with the two upper petals; three enter the