CHAPTER X 



frequented by all sorts of insects, many of them quite useless to the 

 plant; but the bee appreciates their hospitality, and I have seen bees 

 lick up the honey still remaining in flowers whose petals had fallen. 

 The fact that the fruits bore themselves into a soft substratum is made 

 more real when children find them imbedded in fleshy fruits or flow- 

 ers, in strawberries or callas, for instance. We have a native Ero- 

 dium and several species of geranium with fruits very similar to the 

 "clocks;" the flowers of these species, except some in the mountains, 

 are small and not easily observed. The flowers of the native Oxalis, 

 too, on account of their "sleepy" habits and scarcity of honey, are 

 not satisfactory for passing observation. There is a variety of Oxalis 

 corniculata, a common garden weed, that has explosive fruits, one of 

 the inner layers of the ovary wall consisting of tissue in a state of 

 tension that is quite apparent to the touch. The garden balsam, Im- 

 patiens, which has such strikingly explosive fruits, is not so commonly 

 cultivated in California as in the Eastern States. 



The so-called geraniums of cultivation are mostly Pelargoniums 

 from South Africa. They are particularly adapted to our climate for 

 many reasons that can be easily thought out; one device, the absorp- 

 tion of moisture by their hairs, was noted in Supplement to Chapter III. 

 Their methods for pollination are striking and easily discerned; the 

 long duration of the clusters should be noted. Only newly opened 

 flowers supply pollen; the anthers drop off usually before the five 

 stigmas begin to unfold. Honey is kept in a "concealed spur," that 

 is, in a tube united with the flower stem, the entrance to which is be- 

 tween the two upper petals; the three lower petals form a platform, 

 the flowers being slightly irregular, and the guest alighting on these 

 petals, or rising from below as humming birds do, must reach over 

 anthers or stigmas to get the honey; hence exactly the same place on 

 the guest's body that, in newly opened flowers, strikes the anthers 

 will, in older flowers, be rubbed against the stigmas. The tube varies 

 in depth in different species, but in our common red, white and pink 

 "geraniums" it is usually quite too deep for bees. Butterfly collectors 

 tell us that they capture many of their finest night moths among the 

 geraniums, and one has but to walk along the residence streets of a 

 city to see the humming birds at work on the scarlet varieties. Other 

 common cultivated species, the ivy-geranium, or the " Lady Wash- 

 ington" for example, may have shorter tubes with honey accessible 

 to bees, and some of them have very striking honey guides. The 

 Pelargoniums produce abundant seed in our climate, the fruits hav- 

 ing precisely the same devices as the filaree. 



The "nasturtium" of cultivation, which is really a Tropaeolium 



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