A Class List of Preparations 295 



GINKGOALES 



65. Ginkgo biloba. Longitudinal sections of endosperm showing archegonia 

 or young embryos. Paraffin 10 /x. 



Sections of microsporangia with nearly mature pollen, 5 /x. 



CONIFERALES 



66. Pinus Laricio. Transverse sections of needles and young stem. Free- 

 hand or celloidin. Safranin and Delafield's haematoxylin. 



67. Pinus Strobus. Freehand sections of well-seasoned wood. Methyl 

 green and fuchsin, or safranin and Delafield's haematoxylin. 



68. Pinus Laricio. Paraffin. Longitudinal section of mature staminate 

 strobilus. Safranin, gentian- violet, orange. 



69. Abies balsamea or Pinus Laricio. Pollen at shedding stage shaken out 

 and imbedded in paraffin; 5 /x. Stain in safranin, gentian- violet, orange. 



70. Pinus Laricio. Paraffin. Ovule with archegonia. Safranin, gentian- 

 violet, orange. 



71. Pinus sylvestris or P. Laricio. Paraffin. Embryos. Cyanin and 

 erythrosin, or safranin and anilin blue. 



GNETALES 



72. Transverse section of stem of Ephedra. Freehand. 



73. Longitudinal section of the ovule of Ephedra. 



ANGIOSPERMS 

 DICOTYLS 



74. Pelargonium. Transverse sections of stem to show phellogen and 

 intrafascicular cambium. Freehand. Endarch siphonostele. 



75. Tilia americana. Celloidin or freehand. Transverse sections of small 

 stems 3 mm. to 6 mm. in diameter. Safranin and Delafield's haematoxy- 

 Un. Endarch siphonostele with annual rings. 



76. Sambucus nigra. Transverse section of primary root to show origin 

 of secondary structures. 



V 



77. Cucurbita. Longitudinal section of stem to show sieve tubes. 



78. Capsella bursa-pastoris. Paraffin. Floral development, 5 /x. Embryos, 

 5 to 10 fji. Stain both in Delafield's haematoxylin without any contrast 

 stain. 



79. Taraxacum officinale. Paraffin. Floral development, 5 /x. Embrj^o- 

 sac, 10 to 15 /x. 



SO. Ranunculus. Longitudinal sections of 3 r oung flowers to show megaspore 



mother cells and megaspores. 

 31. Silphium. Longitudinal sections of the ovule at the fertilization period. 



Longitudinal sections of staminate flowers just before the shedding of 



pollen. 

 82. Anemone patens. Paraffin. Embryo-sac. 



