101 

 or rasp." I have observed these windows in several of our 

 species — small white lady's slipper {Oypripedium candi- 

 dum) large yellow [C- pubescens) and perhaps also occur- 

 ring in other species. 



Mueller thus describes the insect's method of going out 

 and in: " These bees, attracted bv the color and perfume 

 of the flower, fly into the slipper shaped lip and lick and 

 bite the hairs lining its floor, which are sometimes covered 

 with small drops of honey. They try for some time to es- 

 cape by climbing up the vaulted sides of their prison toward 

 the orifice that they entered by; at last, after creeping be- 

 neath the stigma; they manage with a great ofFort to escape 

 by one of two small lateral openings at the base of the lip; 

 in doing so they smear one shoulder with a sticky pollen 

 from the anther immediately above. In the next flower, the 

 bee, as it creeps under the stigma, leaves some pollen on its 

 papillae, which are long and point obliquely forwards; then, 

 squeezing itself again through one of the small orifices, it 

 acquires another load of pollen; cross-fertilization is thus ef- 

 fected reeularly." He found chiefly Andre?ia. 

 V^ Delpino believes the C. harhatum is pollinated by flies 

 and that C. caudatum is pollinated by snails. Weed states 

 that he found Halictus pollinating flowers of C. acaule, the 

 Pink Lady's slipper. The pollination of this species is de- 

 scribed by him as follows: "The most striking part of the 

 latter (the blossom) is the pouch-shaped labellum, projecting 

 forwards and downwards. This curiously shaped organ con- 

 sists of a large inflated sac, with the front edges inflected in 

 such a way as to form a slit-like opening." 



"The inside of the bottom of the labellum is furnished 

 with hairs projecting upward and backward. Many of them 

 are tipped with a glutinous secretion, which is believed to be 



