CALIFORNIA PLANTS IN THEIR HOMES 



sees the paler flowers of the shrubby Mimulus visited, but 

 perhaps the night moths pay them frequent visits; they 

 could find them easily. The red flowers seem to be visited by 

 humming birds more frequently than the other varieties ; 

 perhaps where the red flowers prevail, it is because they are 

 near humming birds' haunts. You will occasionally see 

 large bees forcing entrance through the closed throat of the 

 other Mimulus. 



But both kinds of Mimulus have excellent devices for 

 making the most of a few visits. Close against the upper 

 lip, or roof, of the flower lie the stigmas and anthers. The 

 stigma consists of two lips, which lie open if the flower 

 has not been recently visited ; touch the lips, and they 

 promptly close ; so, if the stigma is touched by a guest's head 

 with pollen on it, what is left there is securely shut in. 

 The anthers are peculiar ; by looking closely r you will find 

 that there are really four of them, each with two cells ; they 

 lie close together, quite below the stigma. Press against 

 them and see how they open and leave pollen on your 

 finger, just as it would be left on the head of a large insect 

 or of a humming bird crowding into the flower to reach the 

 honey. Notice that the Mimulus needs but four stamens 

 and one pistil. You will find that all plants of high rank 

 are economical. The members of these bilabiate families 

 have rarely more than four stamens, and many of them 

 succeed with only two. 



The Collinsia, Fig. 53, sometimes called innocence, 

 belongs to the same family as the Mimulus. It, too, has a 

 bilabiate corolla, four stamens and one pistil. The lower 

 lip, of course, consists of three united petals, but the mid- 

 dle petal is folded so that it resembles the keel of the 

 lupine; in fact, it serves the same purpose; it enfolds the 

 stamens and pistil, protecting the pollen and stigma, but 

 when a bee alights on the lower lip, the fold spreads enough 

 to allow pollen or stigma to rub against its body. The 



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