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A TEXTBOOK OF THEORETICAL BOTANY 



Herbivorous animals, browsing on herbaceous plants, swallow large 

 numbers of dry seeds and fruits, but their food is normally so thoroughly 

 masticated that only a few of these seeds escape destruction. Nevertheless 

 even cereal grains, such as Oats, do pass through safely, and germinating 

 in the excreta produce well-nourished seedlings. Nitrophilous species like 

 Urtica dioica and Polygonum aviculare are generally dispersed in sheep 

 droppings and are to be found abundantly wherever sheep congregate. 



Seeds of many species of Acacia are difficult to germinate and are greatly 

 improved in this respect by passage either through goats or elephants, 

 which readily eat the pods. Elephants are great travellers and as they eat 

 many kinds of fruits, their excreta often abound in germinable seeds. The 

 Indian elephant eats fruits of Mimusops and Dillenia and also the elephant 

 grass, Themeda gigantea, as well as Mangoes, Rice and other cultivated 

 plants when it can get them. The African elephant eats Acacia pods, 

 Tamarindus, Adansonia, many species of Grewia, and above all the fruits of 

 Borassus aethiopiim, the Palmyra Palm, the seeds of which, though extremely 

 large, are passed unharmed and germinate in the droppings. 



Storage of seeds or fruits by Squirrels and Chipmunks is another means 

 of dispersal, as the hoards are sometimes forgotten and may germinate 

 where they have been hidden. Birds may scatter seeds without swallowing 

 them, by pecking and shaking the soft parts of the fruit, as they do with 

 Rose fruits, or the seeding catkins of Betiila, which are worried by the tits 

 while eating the fruits and many winged akenes are thus launched on the air, 

 though many are also eaten and destroyed. 



In the same manner as the insects are attracted by the colours of 

 flowers, so birds are attracted by the colours of fruits, and, as in flowers. 



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Fig. 1389. — Clerodendron trichotomitm. Verbenaceae. Dark 

 blue berries surrounded by the red, fleshy sepals. 



bright colours are often combined, making them more conspicuous by 

 contrast. Frequently it is an aril which is coloured; shiny black seeds being 



