384 METHODS IN PLANT HISTOLOGY 



GINKGO ALES 



65. Ginkgo biloba. — Longitudinal sections of endosperm showing archegonia 

 or young embryos. Paraffin 10 n. 



Sections of microsporangia witli nearly mature pollen, 2-5 n. 



CONIFERALES 



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

 hand. Safranin and light green. 



67. Pinus strobus. — Freehand sections of well-seasoned wood. Safranin and 

 Delafield's haematoxylin. 



68. Pinus laricio. — Paraffin. Longitudinal section of mature staminate stro- 

 bilus. Safranin, gentian violet, orange. 



69. Abies balscmea or Pinus laricio. — Pollen at shedding stage shaken out 

 and imbedded in paraffin; 5 ju. Stain in safranin, gentian violet, orange. 



70. Pinus laricio. — Paraffin. Ovule with archegonia. Safranin, gentian violet, 

 orange. 



71. Pinus sijlvestris or P. laricio. — Paraffin. Embryos. Cyanin and erythro- 

 sin, or safranin and anilin blue. 



GNETALES 



72. Transverse section of stem of Ephedra. Freehand, steam method. 



73. Longitudinal section of the ovule of Ephedra. 



ANGIOSPERMS 

 DICOTYLS 



74. Pelargonium. — Transverse sections- of stem to show phellogen and intra- 

 fascicular cambium. Freehand. Endarch siphonostele. 



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

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

 toxylin. Endarch siphonostele with annual rings. 



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

 secondary structures. 



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



78. Capsella bursa-pastoris.—Peivsiffin. Floral development, 5 m- Stain in 

 Delafield's haematoxjdin, without any contrast stain; or in iron-alum 

 haematoxylin and orange. 



79. Erigeron philadelphicus and Taraxacum officinale. — Paraffin. Floral de- 

 velopment, 5 n] megaspores, 10 m; embryo sac, 10 ,u. 



80. Ranunculus. — Floral development, 5 m; megaspore mother-cells and 

 megaspores, 5 m; embryo sac, 10 m- 



81. 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, 10 m- 



