1876.] 355 [Meetings. 



showed the peculiar contrivances to insure cross-fertiliza- 

 tion. 



The anthers cohere by the interlacing of their marginal fibres, 

 thus forming a sac which contains the pollen. 



One of the five stamens has a stout filament, which is in a state of 

 tension, and which, when the anther sac is touched, flies forward 

 and over the mouth of the corolla tube; the pollen at the same 

 time being hurled from the flower. After some hours this filament 

 relaxes and bends back, thus opening the orifice of the corolla tube. 



The style is but one half the length of the slender corolla tube, 

 hence it is impossible for pollen from one flower to reach the stigma 

 of the same flower. 



Mr. Charles Wright, who had studied the plant in the 

 vicinity of Rio Janeiro, said that Fritz Miiller had ascribed 

 the task of fertilizing Posoqueria to small insects. Mr. 

 Wright could not agree with this conclusion, and believed 

 the duty was performed by some long-tongued hawk-moth. 

 He observed that a few flowers were fertilized in the green- 

 house at Cambridge, but probably by some accident. 



Mr. Sereno Watson suggested the possible explanation that 

 pollen reached the stigmas of flowers from which the corollas 

 had fallen. 



It was voted to meet for the present every Monday after- 

 noon at 4 o'clock. 



Section of Botany. May 15, 1876. 

 Dr. J. C. White in the chair. Forty-one persons present. 



Mr. Charles Wright made some remarks on the position of 

 the stamens in the Golden Saxifrage (Chrysosplenium) which 

 has been differently described by different authors. Careful 

 study had shown him unmistakably that the stamens are in- 

 serted on the calyx and not on the disk. 



