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106 and anther,—and in some other respects, we have a clear affinity with Spiranthes. In the anther having a broad filament we see a relation to Cephalanthera. In the structure of the rostellum, with the exception of the sloping sides, and in the shape of the labellum, Goodyera resembles Epipactis. Goodyera probably shows us the state of the organs in a group of Orchids, now mostly extinct, but the parents of many living descendants.

Spiranthes autumnalis.—This Orchid with its pretty name of Ladies'-tresses, presents some interesting peculiarities. The rostellum is a long, thin, flat projection, joined by sloping shoulders to the summit of the stigma. In the middle of the rostellum a narrow vertical brown object (fig. 17, C) may be seen, bordered and covered by transparent membrane. This brown object I will call "the boat-formed disc." It forms the middle portion of the posterior surface of the rostellum, and consists of a narrow strip of the exterior membrane in a modified condition. When removed from its attachment, its summit (fig. E) is seen to be pointed, with the lower end rounded; it is slightly bowed, so as altogether to resemble a boat or canoe. It is rather more than $4⁄100$ of an inch in length, and less than $1⁄100$ in breadth. It is nearly rigid, and appears fibrous, but is really formed of elongated and thickened cells, partially confluent.

This boat, standing vertically up on its stern, is filled with thick, milky, extremely adhesive fluid, which, when exposed to the air, rapidly turns brown, and in about one minute sets quite hard. An object is well glued to the boat in four or five seconds, and when the