CHAPTER XXIV 

 SPERMATOPHYTES 



In variety of form and in display of individuals, this group sur- 

 passes all others. We cannot hope to give even approximately 

 complete directions for making preparations, but must be content 

 to give a few hints which may prove helpful in collecting material 

 and in securing mounts of the more important structures. We 

 shall consider the gymnosperms and the angiosperms separately, 

 although in many respects the technic is the same for both. 



GYMNOSPERMS CYCADALES 



Material of cycads is becoming somewhat more available and 

 some stages in the life history can be found in the conservatories of 

 city parks and in botanical gardens. In many species the develop- 

 ment of the ovule, and even the development of the female game- 

 tophyte up to the fertilization period, takes place quite naturally 

 in the greenhouse, where pollination is not likely to occur. The 

 development of the staminate cone and pollen is perfectly natural 

 under greenhouse conditions. The vegetative structures are natural 

 enough, but, with the exception of leaves and small roots, are not 

 so available, since material of the stem would mean damage to the 

 plant. 



The Vegetative Structures. -All the vegetative structures cut 

 rather easily. 



The stem. -Zamia, 1 which grows in various parts of Florida, is 

 the most available material. Directions for handling the stem are 

 given on p. 125. 



Stems of the larger cycads are not likely to be obtained, except 

 in the field, and they are confined to tropical and subtropical regions. 

 They cut better while fresh; consequently, if one can get material, 

 it is a good plan to send it to the laboratory and have it cut before 



1 Material of Zamia pumila can be obtained at 50 cents a plant (express collect) by 

 addressing Mr. Donald Murray, Hawks Park, Florida. 



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