Beer, Development of the pollen grain and anther of some Onagraceae. 29 i 



II. The stamens from anotlier bud were examined in 



1. 0,75% Na Cl. 



Pollen grain = 62 // . 68 //, ^) 



„ cavity = 36 f( . 36 



„ protoplast = 24 // . 30 



2. Egg-wliite. 



PoUen grain = 62 fi . 70 



„ cavity = 36 ,</ . 36 

 „ protoj)last = 26 // . 32 



ff- 



Strong rienimings Solution. 





ff, 

 ff- 



Pollen grain = 64 ^f/ . 70 



„ cavity = 38 ft . 40 

 „ protoplast = 26 // . 30 



4. Merkels Solution. 



Pollen grain =-^ 66 //, 



„ cavity = 40 ^«, 

 „ protoplast =^ 40 u. 

 Tliis caused the protoplast to swell up. 



5. Strong chrom-acetic Solution. 



Pollen grain = 66 //, 



,, cavity = 36 ,</, 

 „ protoplast = 28 f/. 



III. Stamens from another bud examined in 



1. 0,75% Na Cl. 



Pollen grain = 80 //, 



„ cavity = 46 f/^ 

 „ protoplast = 32 [i. 



2. Examined in a drop of juice squeezed from the stem 

 of Oenofhera Jougiflora. 



Pollen grain = 76 // . 76 // . 80 //, 



„ cavity = 42 ^i . 44 // . 46 //, 

 „ protoplast = 32 f/ . 36 f/ . 34 //. 



3. In 5% cane-sugar Solution. 



Pollen grain = 72 ft. 



„ cavity = 42 [a, 

 „ protoplast --^ 30 //. 



IV. In another bud pollen examined in a drop squeezed from 

 stem of Oenofhera longifiora. 



Pollen grain = 72 //, 



„ cavity = 42 ,w, 

 „ protoplast = 34 //. 



V. In another bud pollen was examined in 

 1. 0,6''/oNaCl. 



Pollen grain = 62 ^, 



„ cavity =- 34 //, 

 „ protoplast = 28 //. 



') The successive numbers ((j"2 u and G8 u in this case) denote measiire- 

 ments of several pollen grains. Each vertical series of figures corresponds 

 to one pollen grain. 



