THE TREE. 7 



is commonly called the seed of Maple, Ash, Elm, Walnut, 

 and Basswood is really the fruit. 



Distribution of Seeds. The seeds of plants are distrib- 

 uted in various ways, the most common of which are (1) 

 by means of floats or wings which buoy the seeds up in the 

 air or water, and (2) by animals. The seeds of Ash, Arbor- 

 vitae, Box-elder, Catalpa, Elm, Maple, Pine, and Spruce have 

 wings which allow them to be blown great distances by the 

 wind, especially when they break loose from the upper 

 branches of high trees during severe winds. The seeds of 

 the Honey Locust are not shed from the pod until after it 

 has fallen, and as the pod is ten inches or more long and 

 spirally twisted it may be blown long distances on level 

 ground or snow crust. The seeds of the poplars and wil- 

 lows have a cottony float attachment which buoys them 

 up in the air. In the case of the Basswood, the parachute- 

 like bract attached to the seed-cluster aids in spreading the 

 seeds by carrying them through the air or along the snow 

 crust. The seeds of Mountain Ash, Wild Black Cherry, 

 Hawthorn, and others are largely distributed by wild ani- 

 mals which eat the fruit and allow the seeds to pass through 

 the alimentary canal uninjured or carry off the fruit and 

 spit out the seeds. Many seeds or seed-vessels have bur- 

 like or sticky coats by which they adhere to animals and 

 are thus carried considerable distances. Very often bodies 

 of water aid in the distribution of seeds, since all that are 

 spread by the agency of the wind and most of those that 

 have fleshy coverings will float on the surface of the water 

 and may in this way be scattered. 



Shapes of Trees. Different species of trees naturally 

 develop different shapes. Some, like Spruces, Tamarack, 

 and Balsam, have a decided tendency to form a strong stem 

 and to take on a conical form in preference to the develop- 

 ment of a crown or head; while others, like the Basswood, 

 Oaks, Maples, and Box-elder, develop their crown in pref- 



