Beer, Development of tlie pollen grain and antlier of some Onagraceae. 313 



Fig. 43—45. Tapetal cells of 0. longiflora to sliow cliromidial fibres (f), 

 degenerating nuclei (d) and intact nuclei (n). Worcesters 

 fluid; methylene blue and fuclisin. 



Fig. 46—49. Interstitial bodies of pollen grain of Gaura Lindheimeri 

 sliowing snccessive stages in its perforation and dissolution 

 by the advancing intine Fig. 46—48 examined in cklor-zinc- 

 iodine Solution Fig. 49 stained with bismarck brown. All 

 üxed with F 1 e m m i n g ■ s Solution. 



Fig. 50. Interstitial bod}^ ofmature pollen grain of 0. ?o«(7?/^ora. Medium 



chrom-acetic. Bismarck brown. 



Fig. 51 and 52. Disintegration of special-motlier-cell-wall. Oen. hiennis strong 

 Flemming. To show tlie flrst-formed laincllae of the wall 

 still left intact whilst the later-formed layers have completely, 

 broken down. Fig. 51 cougo red stain. Fig. 52 corallin soda. 



