APPENDIX. 



COLLECTION AND PRESERVATION OF MATERIAL. 



Spirogyra may be collected in pools where the water is 

 present for a large part of the year, or on the margins of large 

 bodies of water. To keep fresh, a small quantity should be 

 placed in a large open vessel with water in a cool place fairly 

 well lighted. In such places it may be kept several months in 

 good condition. 



Some species of vaucheria occur in places frequented by 

 oedogonium or spirogyra, while others occur in running water, 

 or still others on damp ground. Frequently fine specimens of 

 vaucheria in fruit may be found during the winter growing on 

 the soil of pots in greenhouses. The jack-in-the-pulpit, also 

 known as Indian turnip, growing in damp ground I have found 

 when potted and grown in the conservatory yields an abundance 

 of the vaucheria, probably the spores of the alga having been 

 transferred with the soil on the plants. When material cannot 

 be obtained fresh for study, it may be preserved in advance in 

 formalin or alcohol. 



Wheat rust. — The cluster-cup stage may be collected in 

 May or June on the leaves of the barberry. Some of the 

 affected leaves may be dried between drying-papers. Other 

 specimens should be preserved in 2% formalin or in 70$ alcohol. 

 If the cluster cup cannot be found on the barberry, other species 

 may be preserved for study. 



The uredospore and teleutospore stages can usually be found 

 abundantly on wheat and oats, especially on late-sown oats 



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