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BOTANICAL GAZETTE 



he began a new serial, Cybele Columbiana, but only one number appeared. 

 His name is commemorated in the genus Greenella and in many specific 

 names— J. N. Rose, Smithsonian Institution, Washington, B.C. 



THE POLLINATION OF ASCLEPIAS CRYPTOCERAS 

 (with one figure) 



Aschpias cryptoceras is one of the largest flowered asclepiads of the 

 Rocky Mountain region, and although it has a large range over Colorado, 

 Utah, Wyoming, and Idaho, it is seldom common. It is not easily for- 

 gotten when once seen 



The general mechanism of a milkweed flower is well known and a 

 brief recapitulation is all that is necessary here. The asclepiadaceous 

 flower appears externally to consist of the usually reflexed petals and 

 sepals and of the so-called "column," which is surrounded by five 

 "hoods" out of which usually arise five hornlike processes. Between 

 the hoods and on the side of the column are five slits which are usually 

 wedge-shaped, having the larger and open end toward the bottom of the 

 column. The small black bodies which are visible externally at the 

 upper end of the slits are known as corpuscula, and to them are fastened 

 by means of hidden bands the adjacent pollen masses or pollinia of 

 two neighboring anther cells, one on either side of the slit. A corpus- 

 culum may be likened to a paper clip and has a wedge-shaped opening 

 on the lower end. 



growing on a loose, barren 

 hillside, with its deep red 

 and pale green flowers, 

 with their wonderful fra- 

 grance and bizarre form, 

 resembling nothing so 

 much as a jewel in a 

 setting. Because of this 

 peculiarity of structure I 

 propose the vernacular 



as being appropriate. 

 The unusual form is of 

 course due to peculiar 

 insect relations. 



: of "jewel milkweed" 



