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MALAXIS PALUDOSA. PART n. 



chambers, which, contain and expel viscid matter with 

 violence on the slightest touch, and the viscid matter 

 sets hard in two or three seconds, and soon assumes a 

 purplish brown tint. So exquisitely sensitive is the 

 rostellum, that a touch from the thinnest human hair 

 suffices to cause the explosion. As the pointed tops of 

 the loose pollinia lie on the crest of the rostellum, they 

 are always caught by the exploded drop. This never fails. 

 So rapid is the explosion, and so viscid the fluid, that it 

 is difficult to touch the rostellum with a needle quick 

 enough not to catch the pollinia already attached to the 

 partially hardened drop, and consequently the slight- 

 est touch of any small insect which enters the flower, 

 suffices to explode the rostellum, and the pollinia which 

 attach themselves to its proboscis are carried by it to the 

 next flower to adhere to the viscid stigma and fertilize it. 

 Mr. Darwin has seen two Hymenopterous insects retreat 

 from one of these plants with bright yellow pollinia on 

 their heads, and Mr. C. K. Sprengel saw an insect of 

 that kind leave pollen upon a stigma. The action and 

 structure of Neottia Nidus-avis is almost identically the 

 same as that of Listera ovata. 



The Malaxis paludosa, or Bog Malaxis, the smallest 

 of British Orchids, is a rare plant, and differs from all 

 of them in having its labellum turned upwards instead 

 of downwards. Its lower margin clasps the column, 

 making the entrance into the flower tubular. In this 

 orchis the upper sepal and two upper petals are re- 

 flexed, to allow insects freely to visit the flower. In 

 many orchids the labellum is properly directed up- 

 wards, but assumes its usual position as the lower lip 

 by the twisting of the ovarium, or pedicel, of the flower. 

 In the Malaxis paludosa, however, the twisting has 

 been carried to such an excess, that the flower occupies 

 the same position it would have held if the ovarium had 

 not been twisted at all, and which the stalk ultimately 



