Suggestions for Laboratory and Field Work to Precede 

 Chapter Twenty-two 



1. Field work or a trip to a greenhouse will help to make clear 

 some of the characteristics of seed plants, and the differences in 

 the plants belonging to the several divisions of the group. 



2. Examine vegetative shoots of pine, hemlock, spruce, cypress, 

 arbor vitae, or other available conifers, and compare their leaves 

 and stems with those of the ferns and angiosperms. 



3. Material collected from one of the conifers in the spring, 

 showing the staminate and carpellate cones, should be studied in 

 the laboratory. Mature cones may be obtained at any time, and 

 they will show the relation of seeds to scales. 



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