DIMORPHIC BRANCHES OF THE BANANA PLANT. 



43 



a terminal whorl of branches above the surrounding vegetation, and 

 thus secure an amount of exposure to sunlight that might not he 

 obtainable otherwise. Though the cacao must be reckoned as one of 

 the shade types of vegetation it does require light. The most vigorous 

 and productive ca- 

 cao trees are those 

 that stand out in 

 full exposure to tin' 

 light, but the soil 

 conditions must be 

 very favoraVjle to 

 enable the trees to 

 thrive Avith full ex- 

 posure. 



DIMORPHIC 

 BRANCHES OF 

 THE BANANA 

 PLANT. 



Although the 

 habits of growth of 

 the banana plant 

 are altogether dif- 

 ferent from those of 

 the shrubby and 

 woody .species pre- 

 viously described, 

 there is a definite 

 dimorphism of 

 branches that has to 

 be taken into ac- 

 count in studying 

 the habits of 

 growth and the 

 problems of culti- 

 vation. Banana 

 planters regularly 

 distinguish between 

 "sword suckers'* 

 and "broad-leaved suckers,'" but the nature and the extent of the 

 differences between the two kinds of offshocjts have not l>een ade- 

 quately appreciated. The effects of external conditions have been 

 supposed to explain the differences, although lx>th kinds of branches 

 are almost always to be found on any well-develope^l plant. 



Fio. 8.- 



■A broad-leavfd sucker of a banana pluut from 

 Costa Rica. fOrratly reduced.) 



198 



