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three outer, known as the sepals, are generally colored. 

 The petals consist of the three parts one of which the 

 upper is larger than the others and occurs, on the lower side, 

 this is known as the labellum and is often produced into a 

 spur-like nectary. In front of the iabelluni occurs the 

 stamen which is united with the pistil. In Cypripedium 

 there are two stamens with the rudiment of a third. The 

 anther has two very distinct cells; the pollen coheres in 

 masses, each of which has a stalk; these masses with their 

 stalks are known as the poUinia. In the genus Cypripe- 

 dium, the pollen is granular. The ovary is produced above 

 the perianth and rises up in the middle of the flower as a 

 column. The stigma is broad and lutingous. The rostel- 

 lum is a mortified stigma; a part of this is removed with the 

 pollen masses and is called the viscid disc. 

 <A / In Cypripedium pubescens, which occurs in rich 

 woods, is offered an interesting object for study. Lady's 

 slipper or moccasin flower, of which there are several 

 species in Iowa, has three spreading sepals; two of them are 

 usually united into one under the lip. The labellum is ar- 

 ranged into a kind of moccasin, hence the common name, 

 Lady's Slipper or Moccasin Flower. The edges are recurv- 

 ed or over-arched. The stamens and pistil are united. We 

 have a peculiar shield-like body which is notched or hollow- 

 ed out, and two fertile anthers. The pollen is not united in 

 pollina. The surface of the stigma is beset with numerous 

 sharp pointed papillae which are for the purpose of holding 

 the pollen. 



Insects are attracted by the color and strong odor and 

 find it an easy matter to get into the flower, but they ex- 

 perience some trouble in getting out the way they entered, 

 since the margin of the lip is rolled in. Prof. Trelease was 



