Fecundation in Orchidea and Asclepiadece. 693 



sion of the flower, at a time when the sexual organs are so 

 placed with relation to each other that the fecundating matter, 

 believed by him to pass from the pollen mass through its caudi- 

 cula, where that part exists, to the gland attached to it, may be 

 readily communicated to the stigma, with which the gland is 

 then either in absolute contact or closely approximated. The 

 more important points of this account may be extended to nearly 

 the whole order, but it is strictly applicable only to Satyrinae or 

 Ophrydeae, a tribe in which Mr. Bauer seems, with Mr. Lindley, 

 to consider the glands as belonging to the stamen and not to the 

 stigma*. In those genera of this tribe in which the glands are 

 included in a pouch or bursicula, he describes and figures per- 

 forations in the back of the pouch, through which the fecun- 

 dating matter is communicated from the glands to the stigma ; 

 and one of the figures is intended to represent a gland in the act 

 of parting with the fecundating matter. 



It is impossible to judge correctly of Mr. Bauer's theory 

 until all the proofs and arguments in its favour are adduced. 

 I may observe, however, that those already published are by 

 no means satisfactory to me. 



* In the second part of Mr. Bauer's Illustrations, which has appeared since this 

 paper was read, the explanation of Tab. 3. fig. 6. is corrected in the following man- 

 ner : 



" For 6. A pollen mass with its caudicula and gland taken out of the anther ; 



" Read 6. A pollen mass witli its caudicula and the internal socket of the stigmatic 

 gland." 



It is evident, indeed, in the second part of the Illustrations, from figures 8, 9, 11, 

 and 12, of Tab. 12. representing details of Satyrium pustulatum, and the drawings of 

 which were made in 1800, that Mr. Bauer must, from that time at least, have correctly 

 understood the origin of the glands in Ophrydeae. There is nothing, however, in any 

 of the figures in Tab. 3. of the first part at variance with their explanations, from 

 which I judged of his opinion. It may therefore be concluded that Mr. Bauer had 

 not examined these explanations before their publication. 



For, 



