20 



I'eouliaritu's in I'oriii iiiav iMKil)le the winds to drive some fruits before tlieiu 

 even after the hitter have fallen to the ground. The light, globular form of som& 

 pine cones when dried enable them to roll readilv. In the case of other forms, 

 the curvature of cylindrical cones or sliglit hooks at the tip of the scales tend 

 to check motion due to gravity, or the influence of winds. Curvature or twist- 

 ing in flat fruits is ol)viotisly an advantage in traveling before winds. 



The time and duration of the fruiting season is a matter of tlie utmost im- 

 portance; especially if what the writer shall suggest in regard to tlie direction of 

 winds for certain regions and seasons shall be found to be true. Plants wliieii 

 fruit tliroughout the season would tend to spread in all directions, while those 

 that ripen their fruit in a single crop at a stated season would be inclined lo travel 

 more in one or a few directions, and occupy i)articular ranges. Darlington always 

 mentions the fruiting season; later authors but rarely, which the writer has often 

 had occasion to regret. 



Dehiscence of fruits may have an important bearing in the matter of seed 

 dissemination. The forceful and sudden discharge of seeds in oxalis and violets 

 makes these plants independent of outside helj), and scatters the seed in all direc- 

 tions. In these cases the seed are discharged slightly upward as well as outward, 

 enabling these plants to ascend, in time, even steep slopes. In violets cleisto- 

 gamous Howers extend the fruiting season through even the hot months of summer. 

 These fruits are produced for the most part under ground, and were they to re- 

 main there, would be of no value in spreading the species; but after ripe the 

 stalk of the pod elongates and elevates the fruit during dehiscence, and the seeds 

 are scattered as in the case of the pods of the ordinary Howers. 



In (Enothera biennix the pods are only partially dehiscent at the top, and 

 remain upright on the i)lant. The top of the plant bends with, and is shaken about 

 by, winds. The seeds are thus scattered about during a considerable interval of 

 time. This brings up the important point relating to the duration of the period 

 seeds and fruits are carried or retained on the i)lant after their maturity. AVIien 

 long, it increases the chances of many of the fruits being carried to coasideral)le 

 di.-tances by winds: it has relation to the direction of travel or dissemination, and 

 may have an imi)ortant bearing on the tlistrlbution or the range of some append- 

 aged seeds which ordinarily would be thought to travel with the caprice of the 

 lightest wind. 



Lidlris ^'(luarronia afl'ords an illustration. In this plant the heavily pliiincd 

 achenes are carried on the dry receptacle till far toward .January. So thi' di>tri- 

 bution of the seeds of this and some other species of Curnponita- is brought about 



