A CLASS LIST OF PREPARATIONS 383 



PTERIDOPHYTES 



LYCOPODIALES 



50. Lycopodium lucidulum. — Transverse section of stem. Paraffin sections. 

 Safranin and Delafield's haematoxylin. 



51. Lycopodium inundatum. — Paraffin. Longitudinal sections of strobilus. 



52. Selaginella. — Paraffin. Longitudinal sections of rather mature strobili. 

 Safranin, gentian violet, orange. 



53. Isoetes echinospora. — Transverse section of stem. Paraffin. Safranin and 

 Delafield's haematoxylin. 



54. Isoetes echinospora. — Paraffin. Longitudinal sections of microsporangia 

 and megasporangia. Safranin, gentian violet, orange. 



EQUISETALES 



55. Equisetum arvense. — Prothallia in Venetian turpentine. Stem-tips in 

 paraffin. Transverse section of stem, 



FILICALES 



56. Botrychium virginianum. — Paraffin. Stain rhizome, stipes, and root in 

 safranin and Delafield's haematoxyUn. Stain sporangia in iron-haema- 

 toxylin. 



57. Protostele. — Use Gleichenia. Cut freehand or in paraffin and stain in 

 safranin and anilin blue. 



58. Solenostele {amphiphloic siphonostele) . — Use Adiantum or Dicksonia punc- 

 tilobula. 



59. Ectophloic siphonostele. — Use Osmunda cinnamomea. 



60. Polystele. — Use Pteris aquilina or any species of Polypodium. 



61. Sporangia. — For development, use Pteris, Aspidium, Cyrtomium, or try 

 any available species. For mitosis, Osmunda is exceptionally good. 



62. Antheridia and archegonia. — Mount whole in Venetian turpentine. Iron- 

 alum haematoxylin. Sections should be 5-10 /x thick. Stain in iron- 

 haematoxylin and orange. 



63. Embryo. — Pteris and Adiantum are good. Cut longitudinal vertical sec- 

 tions 10 M tliick. 



SPERMATOPHYTES 



GYMNOSPERMS 

 CYCADALES 



64. Zamia. — Freehand sections of steal. Safranin and light green. Trans- 

 verse sections of microsporophyll, 5 or 10 m- Longitudinal sections of en- 

 tire ovule, 10-15 m; stain in safranin, gentian violet, orange. Longitudinal 

 sections of nucellus with pollen tubes, 3-10 m- Iron-haematoxylin and 

 orange. 



