MATERIAL, APPARATUS, AND SUPPLIES 



LISTS OF PEEPARATIOJSTS FOE, THE MICROSCOPE 



211. Slides of value in studies on the plant cell. 



Spirogyra. To show the nucleus : filaments, fixed In weak chrom-acetio 

 acid (Sec. 172, A), stained in iron-alum hasmatoxylin (Sec. 182), mounted in 

 glycerin (Sec. 188) ; or stained in Magdala red and anilin blue and mounted 

 in Venetian turpentine (Chamberlain, Methods of Histology, p. 81, 1905). 



Root tip of onion or hyacinth. For the study of cell and nuclear division : 

 fixed in medium chrom-acetic (Sec. 172, B), or weak Flemming (Sec. 173, A), 

 sectioned in paraffin from five to seven micromillimeters thick, stained with 

 safranin and gentian violet (Sec. 199, D). 



Pollen mother cells of the lily or related types. Also excellent subjects 

 for the study of cell and nuclear division (see Lilium in next section). 



212. Slides of value in type studies. The following list of preparations is 

 merely suggestive ; many other subjects may be added. It is a mistake to 

 suppose that permanent preparations are necessary for type studies. They 

 will, however, at times be of great assistance. The accumulation of class 

 preparations requires time and patience and their proper use demands 

 judgment. There is much danger in giving slides to students before they are 

 prepared to imderstand from studies on living or preserved material the 

 topography and significance of the structures shown in the preparations. 



Volvox. Whole colonies, safranin or iron-alum hsematoxylin, carried with 

 care into balsam (Sec. 187), the cover glass supported by two strips of paper 

 to prevent crushing. 



Ulothrix, or other alga, forming zoospores. Iron-alum hsBmatoxylin and 

 safranin (Sec. 182), carried with care into balsam. 



CEdogonium. Iron-alum hsematoxylin and safranin, glycerin, or carried 

 with care into balsam. 



Coleochcete. Fruiting thallus, Delafield's hsematoxylin (Sec. 183), balsam. 



Fucus. Paraffin sections of oogonial conceptacles to show histological de- 

 tails, safranin and gentian violet, orD.'s hsematoxylin. 



Sporodinia or Rhizopus. Zygospores with mycelium slightly stained with 

 D.'s hsematoxylin, glycerin, or balsam. 



Albugo. Paraffin sections of (1) blisters, D.'s hsematoxylin ; (2) tissue with 

 pogonia, safranin and gentian violet. 



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