BOTANICAL TKIiMS. 



29 



Pollen- : the minute grains (alike in the same plant, but very 

 different in different plants) contained in tljo anther-cells, 

 commonly reseml)ling a loose dust or powder (Fig. 110), 

 but sometimes cohering in sticky masses (pollinia), as 

 in Orcliis (Fig. 149). 



Pollen-grains are plant-cells having t\\., ..mi>, uihI 

 enclosing a thickish liquid. Fig. IwO shows a single 

 pollen-grain with its inner coat growing out in the form 

 of "a tube. 



The pollen is the cs.scnti.il part of the stamen. The 

 pupil should examine with a good microscope various 

 kinds of pollen-grains, aiul make drawings of llicin. 



Number. 



If the stamens are not more than f< ,i in numijcr, the exact 

 number should be stated. If more than ten, they are 

 numerous or indefinite, and this is indicated by tlje sign 

 cc in the proper column of the descriptive table. 



Cohesion. 



If the stamens are entirely separate from each other, their 

 cohesion (or the absence of it) is described by prefixing 

 to the ending -androus the Greek prefix corresi)onding to 

 the number of stamens present, as follows : 



hrpt- 



The cohesion is 



DiDVX.VMOUS : if there are four stamens, two long and two 

 short (Fig. 151). 



Tetradynamous : if there are six stamens, four long and two 



short (Fig. 152). 

 MON'ADELPHOUS : Avhen all the filaments are grown together, 



leaving the anthers separate, as in Mallow (Fig. \'o?>). 

 DiADELPHOu.s : when the filaments are grown together in two 



sets, as in Pea (Fig. 154). 

 Triadelphous : when the filaments are grown together in 



three sets, as in St. John's Wort (Fig. 155). 

 Polyadelphous: when the filaments are grown together in 



more than three sets. 

 SyxCtENEsious : when all the anthers are grown together, 



leaving the filaments separate, as in Dandelion (Fig. 155). 



Adhesion. 



HvpOGYNOUS : when inserted on tli>> nn'oiUafle undor thn 



ovary (Fig. 132, s). 

 Perigynous : when inserted on the catyx (Fig. 133, .«>. 



Fi(,'. IVJ. 



Fig 150. 



Fig. 152. 



Fig. l.-iS. 



Fig. 151. 



Fig. 155. 



antli< ; 

 filaments — 



TlK. l.-w?. 



