LEAKE AND HAM PRASAD 133 



duced with the object of transferring the long staple of the mono- 

 podia! Type 3 to a plant having the synipodial habit, a knowledge 

 of the exact conditions which determine the length of the vegetative 

 period is essential. 



In the axil of the leaf of the cotton plant thei-e occur two buds, 

 one main bud to which the second is accessory. A^egetative growth 

 is effected by the development of a monopodium from either of 

 these two buds. Reproductive growth is effected by the develop- 

 ment of a sympodium from the former bud only. According as the 

 secondary branch derived from the main bud in the axil of the leaf 

 of the main stem develops into a sympodium or a monopodium, so 

 will the appearance of the first flowers be accelerated or retarded, — 

 in other words, the length of the vegetative period is controlled 

 by the form of the secondary branches. If these branches are all 

 monopodial, the appearance of the first flower will be delayed until 

 the appearance of tertiary, or even more remote, branches. If, 

 on the other hand, the early secondary branches are synipodial 

 the first flowers will appear at a very early stage and the vegetative 

 period will be reduced to a minimum. The extreme types are well 

 illustrated in Plates III & VI. This inter-relation between the tvpe of 

 branching and the length of the vegetative period was first noted by 

 Thompson (30) in 1841. A similar inter-relation has been indicated 

 by Balls (1) in the case of Egyptian and American Upland forms. 

 The same point has more recently been recorded by Cook (6, 7, 8). 

 In the latter publication it is stated that all the branches that bear 

 flowers and fruit before again branching come from lateral or extra- 

 axillary (accessory) buds.* This statement is in direct contradic- 

 tion to our own observations, according to which the main bud may 

 give rise to monopodial or synipodial branches, while the accessory 

 bud when it develops, invariably! gives rise to a monopodium. J 



* See also McLachlan Bull. 24!i, Biucaii of Plant Industry, U. S. Depf. of Agriculture. 



t In the Indian types. It is generally true of all types, but we have observed forms of G. 

 hirsutum in which the synipodial secondary branch produces lateral sympodia. As the sympo- 

 dium is itself built up by the growth c)f the main axillary bud, the terminal bud formin" the 

 Hovver, this lateral branch, which arises apparently in flu' axil of the leaf, is dovclo|>od from the 

 accessory bud. 



+ See postscript, page l;^l^. 



