360 Transactions. — Botany. 



below was almost wholly surrounded by its former epiphytal 

 foster-child, a stout spreading specimen of Panax arborea, 

 from which or out of which the fern- tree luxuriously grew as 

 if it were springing from a large vase. On the one side (or, 

 rather, speaking correctly, on three sides) the tree fern was 

 wholly enclosed." 



I am not aware whether any other botanist since Mr. 

 Colenso's time has drawn attention to this peculiar habit of 

 growth of Panax arboreum, or whether it is of frequent occur- 

 rence, but I have noticed so many examples of this curious 

 combination that I thought it might prove of some interest 

 once more to draw the attention of the students of plant-life 

 of our country to this subject. 



For some reason which I am unable to explain Panax 

 arboreum is almost invariably an epiphyte on the stems of 

 tree ferns in the forest regions around Mauku. In open 

 Leptospermum scrub, on banks of streams, and on declivities, 

 when tree ferns are not present, Panax grows as a standard. 

 As an epiphyte Panax arboreum may be seen as a seedling 

 a few inches high, as a sapling a few feet high, or as a tree 

 20 ft. high. The roots of the seedling appear to strike 

 inwards among the damp fibrous remains of old stipes until, 

 reaching the hard inner coating of the caudex, their further 

 inward progress is barred. One root, which I take to be the 

 tap-root, now begins to make its way earthwards, usually in a 

 more or less straight line, though occasionally they appear to 

 progress spirally. As the young tree increases" in stature 

 other roots are given off from the original base of the Panax — 

 i.e., from the point on the trunk of the tree fern where the 

 seed germinated. In some cases these roots follow the line 

 of the first ; in others they appear to grow for a time laterally 

 before descending. With increased growth of the tree the 

 roots become so crowded together that they grow one into 

 another and coalesce, forming a continuous mass of what for 

 want of a better name I have called " root-stems," for by 

 this time they have ceased to be roots, and true roots are now 

 developed in the soil round the base of the fern-tree. While 

 the "root-stems" have been growing downwards the upper 

 stem has ascended, in some cases in line with the fern-tree, in 

 others at a greater or less angle with the caudex. In some 

 cases the "root-stems" have entirely enveloped the caudex 

 of the fern-tree for 5 ft. or 6 ft. above the ground, and have 

 grown so closely together as to present the appearance of 

 a solid Panax trunk, thus giving the appearance of a 

 growing from an urn, referred to by Mr. Colenso. In other 

 fern-tree cases they have formed a more or less open net- 

 work, through the meshes of which the caudex of the fern- 

 tree is visible. 



