COLLECTION AND PRESERVATION OF MATERIAL. 717 



scatter, and be preserved dry. Other stages of the development 

 of the female cones should be preserved either in 70$ alcohol or 

 in 2\% formalin. The male cones should be collected a short 

 time before the scattering of the pollen, and be preserved either 

 in alcohol or formalin. 



Angiosperms. In the study of the angiosperms, if it is de- 

 sired to use trillium in the living state for the morphology of the 

 flower before the usual time for the appearance of the flower in 

 the spring, the root-stocks may be collected in the autumn, and 

 be kept bedded in soil in a box where the plants will be sub- 

 jected to conditions of cold, etc. , similar to those under which 

 the plants exist. The box can then be brought into a warm 

 room during February or March, a few weeks before the plants 

 are wanted, when they will appear and blossom. If this is 

 not possible, the entire plant may be pressed and dried for the 

 study of the general appearance and for the leaves, while the 

 flower may be preserved in 2\% formalin, of course preserving a 

 considerable quantity. Other material for the study of the plant 

 families of angiosperms may be preserved dry, and the flowers 

 in formalin, if they cannot be collected during the season while 

 the study is going on. 



Demonstrations. Upon some of the more difficult subjects in 

 any part of the course, especially those requiring sections of the 

 material, demonstrations may be made by the teacher. The ex- 

 tent to which this must be carried will depend on the student's 

 ability to make free-hand sections of the simpler subjects, upon 

 the time which the student has in which to prepare the material 

 for study, and the desirability in each case of giving demostra- 

 tions on the minuter anatomy, the structure of the sexual organs 

 and other parts, in groups where the material should be killed 

 and prepared according to some methods of precision, now used 

 in modern botanical laboratories. The more difficult demonstra- 

 tions of this kind should be made by the instructor, and such 

 preparations once made properly can be preserved for future 

 demonstrations. Some of them may be obtained from persons 

 who prepare good slides, but in such cases fancy preparations of 



