and Laboratory Methods. 



1885 



Plant Preparations for Museums and General Demonstration 



Work. 



Every teaching botanist recognizes the value of fresh plant material in the 

 work of class instruction ; in most schools, however, fresh material is least avail- 

 able at the season of year when most needed, and in city schools is always more 

 or less difficult to procure, so that the next best material in point of utility and 

 economy is a useful supply of plant preparations. For some purposes it is even 

 true that a skillfully mounted preparation is more valuable than fresh plant 

 material which has not been carefully collected. That plant preparation is the 

 best substitute for fresh plant material which best preserves the natural form and 

 color of the object from which it was made. In the case of leaves and twigs 



Fig. 1. — Fucus vesiculosus. 



Fig. 2. — Zea mais. Stalks with adventi- 

 tious roots. 



good preparations are often made by carefully pressing and mounting the objects 

 on heavy paper, but in the case of fleshy plants or organs different means must 

 be used and the object is then usually mounted in some preserving fluid. Con- 

 siderations of economy and utility require that the preparation be not removed 

 from the medium in which it is preserved ; aside from the inconvenience, the 

 necessary handling will inevitably tear and break up the material. 



A good preparation should also have the element of beauty ; it may be useful 

 and even valuable from a scientific standpoint without being beautiful. Not a 

 little time and pains are often necessary in the selection of specimens in order to 



