42 



• 



More details, with figures, reproduced from Darwin, are given on S. aulumnalis, in 

 Baldwin's " Orchids of New England." The same work contains on Listera ovata a similar 

 extract, also'illustrated, from Miiller who saw a Coleopterous insect and several different 

 Ichneumonidae fertilise the flowers. We have yet to discover what insects render the 

 same service to the Canadian Listera cordata and L. convallarioiodes. As Epipactis 

 gig anted is found in the west, I add here that wasps, honey-bees, and flies fertilise two of 

 its European congeners. Another species is, however, known to be self-fertilising. 



After these several genera common to both sides of the Atlantic, we come to three 

 others, more interesting to us, as they do not occur in Europe. Arethusa, Calopogon, and 

 Pogonia, belong also to a different subtribe, the Arethuseae, in which the very short 

 rostellum has no viscid gland, and the lid-like anther is inverted above it, so as to bring 

 next to the rostellum that end of the pollinia which, in most Orchids, is turned in the 

 opposite direction. The other end of the pollinia is, however, viscid as usual, but point- 

 ing towards the back of the column. How this viscidity originates at such a distance 

 from the rostellum, is, I believe, not yet understood. The anther does not open of itself 

 as in the before mentioned Neottieae, but remains tightly closed in the clinandrium, until 

 some force applied on its edge in an outward direction, lifts it out, swinging on its elastic 

 hinge-like filament. If released, it immediately falls back into its place, provided it has 

 not been too roughly handled. 



I have as yet seen only Calopogon pulchellus and Pogonia ophioglossoides, whose large 

 and lovely flowers appear to such advantage on the tender green of the bog-mosses. The 

 structure of the latter has been well described by Dr. S. H. Scudder in an article in the 

 proceedings of the Boston Society of Natural History (1863), which is also to be found 

 in Mr. Baldwin's book. The column lies over the lip by which it is partly enclosed, but 

 there is left under it a kind of tube through which the visitor may with some effort creep 

 first under the anther, then under the long stigma, and finally reach the peculiarly per- 

 fumed nectar at the bottom of the tube. The insect, on withdrawing, brushes against the 

 fringed lid of the anther, and inverts it, thus bringing the upper viscid ends of the pollinia 

 down against, its back ; and if they stick fast to its body, it is enabled to perform the 

 pollination of other stigmas. The anther is remarkably thick and massive: the pollen cells 

 form but a very small part of its volume. Hence, after having been raised it falls by its 



it into its first position, and the cells are thus brought back into the clinandrium 

 which shelters them perfectly as before. Consequently, if all the pollen has not been 

 taken away by a first visitor, it may be by a second. The insects must evidently be 

 rather small to be able to pass under the column, and, further, must be winged, for 

 entrance by creeping up the stem and the sides is prevented by the petals and sepals, 

 while, on the other hand, the lip spreads forward, carpeted with fringes, as a most con- 

 venient alighting place for winged visitors. 



The flower of Calopogon is very differently disposed, all the parts being widely 

 expanded and separate. It is unique among Canadian orchids, in that its ovary does not 

 twist when the flower opens, so that the lip keeps the same position that it had in the bud, 

 and remains the highest part of tlie flower. The sepals and lateral petals are lanceolate 

 and about equal. The lip, which is a little shorter, widens out above into a vexillum 

 similar to that of some Leguminosae, but its anterior face is ornamented with white and 

 yellow hairs, which contrast beautifully with the brilliant purple of the rest of the flower ; 

 and the whole cannot but attract from afar the attention of insects in quest of booty. 

 The lip is articulated a little above its base, where in the bud it is folded at a right angle 

 while lying over the column. When the flower expands, the lip is the last part of the 

 perianth to open out. It then becomes erect and keeps that position for three or four 

 days. Then only can the pollinia be withdrawn from the anther, and fertilisation take 

 place ; for afterwards the lip falls down again into its original position on the column and 

 covers up both the stigma and the anther. 



The winged petaloid column projects ferward : it is peculiar both for its length and 

 for the small dimensions of the anther and the stigma, which form a scarcely noticeable 

 swelling at the truncated extremity. The inner and upper surface of this swelling is the 

 stigma, under which the anther rests in the clinandrium. A slight outward pressure on 

 tke edge of the lid opens it, and it is seen to be divided by a thin partition into two cells, 



