Korthalsia. KORTHALSIA. 105 
(K. scaphigera, scaphigeroides, Echinometra, horrida, Cheb, angustifolia, Scortechinit, furcata). 
Regarding the biology of  Korthalsia I refer the reader to my article on the 
* Piante ospitatrici’’ (Malesia, ii, p. 62). In K. robusta and K. macrocarpa, the 
ocreae do not form an entirely closed. dwelling for ants, but take the shape of 
large cornets embracing the base of the ‘sheaths immediately above them, and at 
times attaining the extraordinary. length of 30 to 40 cm. In most species, however, 
the ocreae are cylindrical, closely sheathing, and often partially disintegrated into a 
fibrous net. The form and peculiarities of the ocrea afford often the best characters 
by which to distinguish the species, even if flowers and fruit be wanting. The , 
nature, origin, and function of the ant-harbouring organs, not only in Korthaisia, 
but in numerous other myrmecophilous plants, and most of all, in Myrmecodia and 
Hydnophythum have been much discussed. With regard to this subject I retain my 
old opinion that, such organs are now hereditary, but that they owed their origin 
to the effects of the stimulus exerted by ants on certain organs of the plants, 
of which the tissues were capable of a. reactive power during the remote 
period of the plasmation Epoch, when heredity had not yet acquired its actual 
conservative power. (See Beccari * Wanderings in the Great Forests of Borneo,” 
pp. 35, 209 and seq.) The Korthalsías have been, for a long time, only very 
imperfectly known, and it was generally believed that they were bisexual plants. 
In reality they have only one kind of amentiform or catkin-like spikes, which at 
times closely resemble those of Metroxylon, but which differ from them in having 
only one hermaphrodite flower in the axillas of very closely packed spathels. 
Although I had for several years made every effort to obtain the flowers and 
fruits of the several species of Korthalsta, there are even now at least 8-4 species 
which are represented in Herbaria only by sterile specimens. This is explained 
by the circumstance that the stems or Rotangs of Korthalsias are very eagerly 
searched for and much valued by the natives, but on account of their monocarpic 
nature are very seldom to be met with im the accessible parts of the forest, 
either in flower or in fruit, for the stems are almost always cut down before they 
can produce the inflorescence. The species of Calamus are more easily found in a 
fertile condition, as they are polycarpic plants, beginning to bear early. 
\ 
The Rotangs or naked canes of Korthalsias being very tough, are very much 
used by the natives for tying and other uses, but have not much value as a 
commercial product, not having a fine and polished surface. 
The Korthalsias are apparently  soboliferous plants, and have like other 
calamoid palms, ‘stems very slender in the early period of their life, but gradually 
thickening with age, their greatest diameter being attained at their upper’ end 
at the time of flowering. 7 
1 
In connexion with the Myrmecophilism of Korthalszas, it has to be remarked 
that apparently certain species are furnished with extranuptial nectaries in the axillas 
of the leaflets, in the shape of conspicuous callosities or cushions; analogous 
ANN. Roy. Bor. GARD., CALCUTTA, VOL. XII. 
