Branner. } 478 [April 18, 
whose trunks are not larger than an ordinary lead pencil, but which, 
having the phylophore comparatively short, have the fibro-vascular bun- 
dles hardened early, and are consequently perfectly upright in habit. 
J have not seen the Asiatic genus Oalimus growing, nor have I been 
able to see any careful description of it, but judging from its slender stem 
and long internodes, I venture to guess that it hag a very long phylo- 
phore, and to suggest that its great length and clambering habit is to be 
explained in this same manner. 
Speaking of palms in general, in the same individual, the length of the 
internodes has much to do with giving it character as seen in its general 
appearance. As the length of the internodes, the age and vigor of the 
plant, and the drooping of the fronds are all intimately related, I will speak 
of these subjects in the same connection. 
The drooping of fronds which is so much more marked in old palms 
than in young ones, in feeble than in vigorous ones of the same species, is 
caused ; 
First. By a decrease of the strength and vigor of the fibro-vascular 
bundles of the midrib. This variation in the strength of the midrib effects 
the drooping of the frond throughout its whole length, 
Second. By the decrease of the vital powers of the whole plant, from 
which it results that the angle made by the outcurving bundles with the 
axis of the stem is larger than in the case of more vigorous growth.* 
This effect can be seen by diagram, figure XI, in which O is the 
point of the phylophore where a frond is originated. In a case of feeble 
growth, the frond would stand out at B, making a large angle with the 
axis of the stem, while in case of vigorous growth, it would stand out at 
A, making a comparatively small angle with the axis. The result of dif- 
ference in growth is very distinctly seen by comparing the young plants 
with old ones of the same species grown on the same soil. In the young 
ones the internodes ure invariably| longer, and just as invariably the fronds 
are more erect. The fronds being continuations of the bundles, the angle 
made by the bundles with the side of the stem is continued into the fronds 
under slight modifications, The effect of this angle upon the fronds is also 
noticeable in the phylophore, for the angle at which the bundles cross the 
periphery being smaller in the cone-shaped apex, the fronds have a more 
nearly erect position, In figure XII, the upper fronds make a smaller 
*fence the angle of drooping in fronds, taken alone, is not always a specific 
characteristic, as stated by Wallace in his ‘‘ Palms of the Amazon,” p. 5. 
} Peculiar circumstances may change this, as I once saw well illustrated in the 
case of a Mauritia flexuosa near Pardé. The whole trunk was about thirty metres 
high, and about six metres below the fronds, the old scars were very close 
together, and the trank had every appearance of having completed its growth 
at that point, Above this, however, the trunk appeared to have renewed its 
youth, and the internodes were long and smooth like those ofa vigorous palm, 
In seeking the possible explanation of this new growth, I found that the place 
where the palm stood had, a great many years before, been a forest, and that it 
had originally stood in the edge of a stagnant pool which had been drained, 
Whether these were the causes of the renewed vitality there were no means of 
ascertaining, but the evidence of that vitality was unquestionable, 
veel 
