286 SMITH : 



An increase in length of 10-12 cms. in one week is thus common 

 in strongly growing new shoots of Theobroma. 



When we consider that in many cases trees, such as Theo- 

 broma, Mesua, Mangifera, &c., are putting on over their whole 

 periphery new growth at this rate, we can understand how great 

 a supply of reserve food is necessary at this period. In working 

 up the reserve starch into plastic material for new growth of 

 leaf and stem, there must be a correspondingly'^ great demand 

 for the mineral foods which are needed to form the protoplasm. 



Very little is known as to how far nitrogenous organic 

 reserves are stored up by trees, and no investigations on this 

 point have been made on the particular trees here in question. 

 Beyond the fact that trees do in some cases store up certain 

 amounts of proteids and amides, scarcely any reliable informa- 

 tion is to be obtained. Turning to the case of reserves stored 

 in seeds we kno^A' that proteids form a part of such reserves in 

 many cases. But in general the proteid and carbohydrate are 

 not in the proportions in which the young plant makes use of 

 them. In germination the radicle, as a rule, is the first organ 

 to elongate, and the development of the other parts does not 

 occur until the radicle is at such a stage that it can supply 

 mineral foods to the young plant to be worked up along wdth 

 carbohydrate into plastic materials for groAvth. 



Godlewski (10), 1879, showed that development of i2apAan.%s 

 seedlings in the dark took place far more vigorously when he 

 supplied them with nutrient salts than when they had distilled 

 water only. If in the rapid growth of the trees under con- 

 sideration a similar state of things holds good, then a copious 

 supply of mineral salts from the soil will be required at the time 

 of growth. 



It must be repeated that whether this is the case or not, 

 whether the growth takes place from reserves of carbohydrate, 

 nitrogenous organic material, and minerals, all stored up in 

 the tree and in the right proportions, or Avhether special 

 demands are made upon the mineral supply from the soil at 

 the time of growth, is not known. 



Shibata (27) has investigated the nitrogenous and other 

 reserve present in the rhizomes of bamboos previous to the 

 very rapid elongation of the young culm in the growing season. 



