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C. U. C. P. ALUMNI JOURNAL 



numerous cross striations. The bark root breaks with a very uneven and 



splits from the center, exposing the ragged fracture. It has no odor, but 



woody tissue which separates radially, has a slightly bitter taste, 

 leaving pieces of shrunken tissue. The 



Asclepias syriaca. 



H.- Starch. B.— Fibers. X— Stone cells. K.— Cork. 



HM. — Parenchyma filled with starch, crossed by medullary rays. 

 C. — Rosette Crystals. V.— Vessels. O. — Parenchyma. 





Most Apparent Historical Differences. 



In a microscopical examination of a 

 powdered sample of Asclepias tuberosa. 

 the most numerous elements are the 

 stone cells, varying in size from .06 to 

 .25 millimeter in length and from .09 to 

 .12 millimeter in width. They are al- 

 most circular, with very thick walls and 

 small empty cavities, circularly striated, 

 ■of light yellow color, and have small 



pores. They occur most frequently in 

 pairs, but are also seen in masses. 



Next in prominence are the large, 

 yellow bast fibers, as m,uch as 2.40 milli- 

 meters in length and .25 millimeter in 

 width, very finely striated and porou^ 

 with a small central cavity. The wallr, 

 are rough and very thick, giving the ap- 

 pearance "of a dark outline surrounding 



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