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CYPRIPEDEÆ—HOMOLOGIES OF THE FLOWERS OF ORCHIDS.

have now armed at Lindley's last and seventh tribe, including, according to most botanists, only a single genus, Cypripedium, which differs from all other Orchids far more than any other two of these do from one another. An enormous amount of extinction must have swept away a multitude of intermediate forms, and has left this single genus, now widely distributed, as a record of a former and more simple state of the great Orchidean Order. Cypripedium possesses no rostellum; for all three stigmas are fully developed, though confluent. The single anther, which is present in all other Orchids, is here rudimentary, and is represented by a singular shield-like projecting body, deeply notched or hollowed out on its lower margin. There are two fertile anthers which belong to an inner whorl, represented in ordinary Orchids by various rudiments. The grains of pollen are not united together by threes or fours, as in so many other genera, nor are they tied together by elastic threads, nor furnished with a caudicle, nor cemented into waxy masses. The labellum is of