CHAPTER XI. 



PLANTS OF HIGH RANK. 



The application of the term rank to plants is not perhaps in strict 

 accord with the theories of modern biologists concerning species. 

 Certainly it is not easy to define what constitutes the highest develop- 

 ment in plants ; but in order to emphasize, in this and in following 

 chapters the differentiation of parts and the division of labor existing 

 in certain groups of plants, the old term " higher plants " is retained. 

 The fact that there are so many different systems of classification, 

 none claiming perfection, and that there is no one plant or plant 

 family that has universal recognition as the highest, is noted in the 

 next chapter. The bilabiate families, Scrophulariaceae and Labiatae 

 are particularly well represented in California in the late spring and 

 summer, and it is very easy to recognize their members ; they have 

 always irregular corollas, two or four stamens, and one style ; the 

 ovary of the Scrophulariaceae is always two-celled, the ovary of the 

 Labiatse, like that of Borraginaceae, separates into four nutlets. Two 

 families might possibly be confused with them ; the family Ver- 

 benaceae, which is commonly represented by a rough, weedy plant 

 with small, crowded, violet flowers, Verbena prostrata> R. Br., 

 and Orobanchaceae, the cancer coot family, which consists of root 

 parasites, and hence is without chlorophyll, the entire plants being a 

 dull, brownish yellow or purple. 



Mimulus glutinosus, Wendl., illustrates well the capacity of flowers 

 for color variation. The most common color is buff or salmon, but, 

 in the mountains I have seen masses of flowers that were hardly more 

 than cream colored, while at Catalina Island I have found the flowers 

 red only. Frequently in the foot-hills one finds, growing in close 

 proximity, plants of this Mimulus with buff flowers, others with red 

 ones, and others in intermediate shades. Bees are quite debarred 

 from the honey of these flowers ; they cannot even bite through the 

 flower, because of the tough, viscid calyx that closely invests the 

 corolla tube. There are small insects that can enter the tube bodily , 



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