APPENDIX II 



LABORATORY DIRECTIONS 



For much more detailed laboratory work than has been outlined in 

 the present book see Bergen and Davis' Laboratory and Field Manual 

 of Botany (Ginn & Company). A series of type studies of spore-plants 

 and of representative species of seven families of seed-plants is there 

 given, and the subject of ecology is treated vpith some care. The 

 selection, preservation, and preparation of material for histological 

 work is carefully described. A glossary of botanical terms is given 

 in the Manual. 



APPARATUS 



The equipment of apparatus necessary for the laboratory and for 

 the individual student is discussed in the Manual. Some special 

 pieces of apparatus may, however, be mentioned in this place. For 

 experiments on the relation of temperature to the germination of 

 seeds, and for determining the highest temperatures which blue-green 

 algae, bacteria, or other organisms can support, it is convenient to have 

 a small, warm chamber, or incubator (thermostat). Such a chamber 

 of 22 X 30 X 22 cm. inside dimensions maybe had of Eimer & Amend, 

 205-211 Third Ave., New York, for $40, and larger ones at higher 

 prices if desired. For some purposes a differential thermostat, as 

 described by Professor W. F. Ganong,^ is still better. 



The apparatus to measure sap pressure (p. 47) may, as suggested 

 by Professor Ganong, advantageously be replaced by a pressure-gauge 

 consisting of a column of air contained in a perfectly cylindrical 

 glass tube, closed at the upper end. Before such a gauge is used 

 Boyle's law for pressure and volume of gases should be explained to 

 the class and experimentally illustrated. 



1 Laboratory Course in Plant Physiology, Henry Hglt & Co., New York. 



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