492 ON THE ORGANS AND :\10I>E Or lECUNDATION 



which convey the absorbed iiiiid iVoin that organ to the 

 ovariuui. 



In 1S04, Sahsbiiry^ asserts that he had succeeded in 

 6^»i inipregnatuig many species belonging to different tribes 

 of Orchidese, by applying the pollen masses to the stigma, 

 Avhose channel commuiiicathig with the cavity of the 

 ovarinm, and first noticed by H alter, he also describes. 



In 1827, Professor L. C. Treviranns^ published an ac- 

 count of several experiments made by him in 1824, whicli 

 satisfactorily prove that impregnation in this family may 

 be effected by the direct application of the pollen to the 

 stigma. 



Abont the end of 1830 a letter from Professor Amici^ 

 to M. Mirbel was published, in wldch that distinguished 

 microscopical observer asserts that in many phccnogamous 

 plants the pollen tubes, or bof/ai'j\ penetrate through i\\{i 

 style into the cavity of the ovarium, and are a})plied directly 

 to the ovula. 



In this important conununication OrchidcEe are not 

 mentioned, but M. Adolphe Brongniart in a note states 

 that he himself has seen the production of hoyaitx or pollen 

 tubes even in this family ; that here, however, as well as 

 in all the other tribes in which he had examined these 

 tubes, he found them to terminate in the tissue of the 

 stigma. 



Of the second class of authors the earliest is Linnaeus,^ 

 who, in 1764, not satisfied cither Avith his own or any 

 other description then given of the stigma, inquires v»hether 

 the influence of the pollen may not be communicated in- 

 ternally to the ovarium. 



In 1770, Schmidel,' in an account which he gives of a 

 species of Epipactis, describes and figures the upper lip of 

 the stigma, the rostellum of Richard, with its gland both 

 before and after the bursting of the anthera ; and as he 



^ Linn. Soc. Transact, vii, p. 29. - Zeitsclirift f. Phi/siol. W, p. 225, 



^ Annal. des Sc. Nat. xxi, p. 329. 



' F reelect, in Orel. Nat. ed. Giseke, p. IS 2. 



^ Gesn. Op. Bot. hist, plant, fasc. ii, p. 15, tab. 19. 



