218 Parkin . — Extra-floral Nectaries of Hevea brasiliensis 
brasiliensis the bud-scales are just mentioned, but their nectariferous nature 
is not pointed out. 
The description to follow is the result partly of observations made 
while resident at the Royal Botanic Gardens, Peradeniya, Ceylon, and 
partly of the examination of some spirit-preserved young shoots from 
adult trees brought back to England. The following account does not 
claim to be at all exhaustive. The object of this paper is chiefly to 
bring to notice a somewhat peculiar type of extra-floral nectary. 
Morphology of the shoot . The adult trees at Peradeniya shed their 
leaves early in the year and remain bare for some days before the new 
foliage appears. On February 16, 1899, the new shoots had almost 
gained their full length, but their foliage leaves were still very immature. 
At this stage of growth the bud-scales are fully developed and their 
nectaries active. On the leaves attaining maturity these structures shrivel 
and drop off. According to Huber 1 the adult trees in their natural 
habitat, the Amazon valley, produce likewise only one crop of leaves 
in the year, but the time they are bare is about June ; hence the trees 
in Ceylon appear to have changed the time of the annual renewal of 
their foliage. This may be due to climate. The early months of the 
year constitute a moderately marked dry season in that part of Ceylon 
where Peradeniya is situated, and dryness is considered to have a direct 
bearing on leaf-fall. Yet on this idea the Hevea trees at Peradeniya 
ought not to burst into fresh leaf till about April, when the rains of 
the little monsoon commence : as it is they renew their foliage about 
the driest time of the year, while they cast off the old in January, a wetter 
and cooler month than either February or March. 
Though mature trees produce only one set of leaves during the year, 
young trees — saplings — put forth several, showing a periodicity, which 
has been described by Huber 2 . Such saplings may produce fresh shoots 
about every month. 
My attention was first called to the nectariferous bud-scales by 
noticing one day insects busy on the young shoots of some saplings 
growing in a plot. At a short distance away they looked as if they were 
devouring the immature foliage, leaving behind the stumps of the petioles, 
but on closer inspection I saw that they were a hairy kind of ant (?) 
imbibing the honey secreted by special foliar organs situated on the lower 
part of the shoot. Owing to the internodes between these structures 
having lengthened considerably, the general impression conveyed a little 
distance away was that of short petioles with the foliaceous part nibbled 
off. The true foliage leaves, however, were quite intact on the upper 
part of the shoot with their laminas as yet feebly developed. My first 
observations were made on these saplings, as I had to wait till the 
1 Huber, loc. cit. 2 Huber, loc. cit. 
