GENERAL EVALUATION 



331 



Fig. 16-2. Chemical components of Yakima and Jefferson pepper- 

 mint oils as revealed by gas chromatography (Permission of 

 Wilkens Instrument and Research, Inc., Walnut Creek, California). 



techniques. That is, relatively crude extracts may be chromatographed 

 wdth different column systems, perhaps with programmed tempera- 

 ture control, to yield a complex chromatogram. Major peaks will be 

 selected for comparison with extracts from other species. Even though 

 the peaks were not immediately identified, the pool of variation thus 

 uncovered should be subject to systematic interpretations. Such a 

 technique should prove quite valuable in the analysis of populations 

 and in studies of natural hybridization. 



Limitations of gas chromatography at present appear to be 



