LABORATORY PRACTICE 



3. Small downward-pointing hooks or barbs (readily visible 



under a lens) . 



4. Make an enlarged sketch to show these points. 



III. Examine the fruit of the Common Bedstraw or 

 Goose Cleavers and notice: 



1. The two small rounded portions (called mericarps). 



2. The hooked bristles with which each is provided. 



3. Make a sketch of this fruit. 



IV. Gather and study all the specimens of fruits which you 

 can find provided with organs for attachment to animals. 



V. But some fruits possess spines which do not appear 

 to serve the purpose of aiding dispersal by animals. The 

 Chestnut, Chinquapin, Beechnut, and Thorn Apple {Datura) 

 are provided with spines surrounding the fruit, but the cov- 

 ering opens, and the seeds drop out. The spines in these 

 cases probably protect the seeds, while ripening, from squir- 

 rels and such animals. (Some ripening berries have spines 

 which fall off when the seeds are mature.) 



VI. Small animals, such as squirrels, store away nuts and 

 grain in the ground and forget the place or are killed. The 

 seeds of these fruits may germinate. This is a very effec- 

 tive means for seed dispersal in some regions, but of rarer 

 occurrence than the other methods. Ants, too, store seeds 

 and fruits in their underground homes. 



