158 Bulletin Ja rd. Bot. Buite nzorg, Série ill, Vol. V. LivR. 2. 



Pond {-^) showed that the endosperm of the date is incapable of 

 self-digestion. 



Kruijff C^) reported that the haustorium of the coconut contained 

 lil)ase, protease, amylase, catalase and peroxidase. 



Structure of the haustorium. 



When the embryo is in the resting condition, that is when the fruit is 

 already ripe, ail the structures which are to function during the process 

 of germination are already deliminated. That is especially true of the 

 haustorium, ail of whose éléments are présent before germination. Thus 

 in cutting cross sections of the resting embryo one finds, as one appro- 

 aches the juncture of haustorium with the cotylédon, the definite arrangement 

 of the vascular bundles in a ring. In a longitudinal section the bundles 

 are seen running to the very end of the cotylédon. Thèse bundles at the 

 opposite end are in communication with the embryo proper. In Figure 132, 

 Plate XVI, ten bundles are seen arranged in a ring. This section was made 

 from the neck-piece of the haustorium where it passes out of the germ 

 pore. The bundles are most closely compressed in the canal running 

 through the shell. Within the shell the bundles spread themselves out and 

 also outside of the shell they are wider apart. In Figure 127 which is a 

 longitudinal section through the seed and seedling three of thèse bundles 

 can be followed from the haustorium into the vascular System of the seedling 

 in an advanced stage of growth. The structure of the bundle in cross 

 section shows an outer zone of cells polygonal in outline with thickened 

 walls. This zone in some places is more than one cell thick. Within this 

 zone are bast, xylem and phloem cells. In its gênerai structure it is like the 

 bundle described in the shell (Figure 79 Plate VIII). The outermost layer 

 of the haustorium, the ferment layer or epidermis, is definitly deliminated 

 in the resting stage of the embryo and can be seen as columnar cells with 

 their long axes perpendicular to the long axis of the haustorium. Inside 

 of this layer follow two or three layers of more or less cubical cells, then 

 come bundle cells and in the center a parenchyma of irregular cells. The 

 innermost tissue which is the spongey tissue of the growing haustorium 

 does not show the inter-cellular spaces in the resting condition. 



As soon as germination sets in changes are observed in the haustorium. 

 Nuclear and cell division go on simultaneously in ail parts of the haustorium, 

 the most active division of cells takes place in the outermost layer and the 

 two, three and sometimes more layers within. Notwithstanding the statements 

 made by SACHS (^') and others that it is the outermost and the second 

 layer that divides, I hâve been able to find nuclear and cell division in ail 

 the régions in a stage shown in Figure 128, Plate XVI. 



The innermost tissue, the spongey parenchyma, in the very first stages 

 of germination begins to expand so that inter-cellular spaces appear between 



