242 DIPPICLTLTIES OF THE THEORY [Chap. VL 



ingenious man, if he had not witnessed what takes place, 

 could never have imagined what purpose all these parts 

 serve. But Dr. Criiger saw crowds of large humble- 

 bees visiting the gigantic flowers of this orchid, not in 

 order to suck nectar, but to gnaw off the ridges within 

 the chamber above the bucket; in doing this they 

 frequently pushed each other into the bucket, and their 

 wings being thus wetted they could not fly away, but 

 were compelled to crawl out through the passage formed 

 by the spout or overflow. Dr. Criiger saw a " continual 

 procession " of bees thus crawling out of their involun- 

 tary bath. The passage is narrow, and is roofed over 

 by the column, so that a bee, in forcing its way out, 

 first rubs its back against the viscid stigma and then 

 against the viscid glands of the pollen-masses. The 

 pollen-masses are thus glued to the back of the bee 

 which first happens to crawl out through the passage of 

 a lately expanded flower, and are thus carried away. 

 Dr. Criiger sent me a flower in spirits of wine, with a 

 bee which he had killed before it had quite crawled out 

 with a pollen-mass still fastened to its back. When the 

 bee, thus provided, flies to another flower, or to the 

 same flower a second time, and is pushed by its com- 

 rades into the bucket and then crawls out by the pas- 

 sage, the pollen-mass necessarily comes flrst into eon- 

 tact with the viscid stigma, and adheres to it, and the 

 flower is fertilised. Now at last we see the full use 

 of every part of the flower, of the water-secreting horns, 

 of the bucket half full of water, which prevents the bees 

 from flying away, and forces them to crawl out through 

 the spout, and rub against the properly placed viscid 

 pollen-masses and the viscid stigma. 



The construction of the flower in another closely 



