1886-87.] Flowers of Bolho'phylhiiin Lohhii. 105 



and each of which consists of two parts joined together like the 

 two cotyledons in a bean. 



The two lateral collar-like expansions are the two stamens 

 of the inner whorl. This can be easily proved by making a 

 transverse section of the column about the region of the 

 stigma, when one finds, first of all, one bundle trace which be- 

 longs to the fertile stamen and two lateral traces belonging to 

 the staminodes. The spiral vessels of the lateral traces are in 

 the same position as the missing stamens of the inner whorl. 



The stigmatic surface (fig. 7, s) in the newly expanded flower 

 consists of a deep depression, at the basal margin of which is 

 the viscid matter in the shape of two protruding drops, lying 

 close side by side. In the upper half of the depression, two yet 

 deeper depressions are to be seen, and these form the stigma 

 proper. The two depressions are either for the two pollinia— 

 but this, however, I don't consider likely, because the pollinia 

 are removed singly — or for the two halves of one pollinium, 

 which seems to be the right explanation, as will be shown 

 afterwards. 



The viscid matter is of great toughness, so that it is possible 

 in rather old flowers to draw out threads 6 to 7 inches long. 

 After the flower has been open for two or three days the viscid 

 matter loses its drop-like appearance, and fills up the whole 

 depression between the two collar-like expansions. 



The hook-shaped prolongation of the column consists of the 

 petiole of the inferior petal, and the filaments of the two 

 remaining stamens of the outer whorl. 



The heart-shaped labellum is fixed to the column by a thin 

 neck (figs. 8 and 9), much compressed in the antero-posterior 

 direction, and freely movable, only, however, from the hori- 

 zontal position into a more or less vertical one. The thicker 

 but short bilobed basal portion is directed towards the centre 

 of the flower, while the apex hangs out as a tongue-like pro- 

 jection. The labellum is curved, more or less, like a half 

 moon ; the superior surface being hollowed out from side to 

 side, and so distinctly concave. On the superior surface of 

 the labellum near the base are three yellow spots; one larger 

 than the others is situated in the middle line above and a little 

 anterior to the junction of the labellum and the column, and 

 the other two at the inner side of the posterior lobes. 



With resfard to the anatomical structure of the column 



