HYLOBATES 159 
sort of kick-off, he flies through the air, seizing another bough and 
swinging along it with the unerring accuracy of a finishel trapeze per- 
former. I fancy he does very little walking in the wild state, for I 
have never seen a wild Hoolock on the ground. Moreover they are 
only found in the dense jungle, where the ground is everywhere covered 
with tangled vegetation. It is puzzling to me why these anthropoids, 
being so entirely arboreal in habit, should be lacking in such a useful 
appendage as a tail. The Hoolocks are extremely shy, and it is most 
difficult to watch them, as they are concealed by leaves high up in 
the tops of the bamboo clumps or forest trees. You may hear their 
cries all around you as you ride quickly along a jungle-tract. but 
the moment you leave the path or look up at them there is a dead 
silence and scarcely a leaf stirs, until. tired of waiting, you move on 
again. The cry of the Hoolock is a characteristic sound in the Cachar 
jungle. It is a very pleasing note, rising and falling in intensity, and 
reminding one somewhat in its rhythm of a pack of beagles giving 
tongue on a scent which is waxing and waning in strength, as a larger 
or smaller number of the band join in the chorus. It is heard chiefly 
in the early morning, then all through the heat of the day there is 
silence, but towards evening as the sun sinks, you may hear it again. 
Hooloo! Hooloo! MHooloo! with the accent on the Hoo syllable, 
is supposed to describe the sound, but it is really quite indescribable in 
writing. As in other species of Apes, there is a special modification of 
the larynx, which acts as a sort of resounding box, and helps, (I sup- 
pose), to make the sound carry, as it does, long distances. There is also 
a peculiar arrangement of the upper aperture of the larynx, with its 
small and inadequate looking epiglottis, which more resembles the 
arrangement in birds than the leaf-like epiglottis in man. 
“As, day after day I have ridden through the jungle, it has seemed 
to me that the Hoolocks worked their ground systematically in their 
search for food, just as the planter plucks one section of his tea to- 
day and another section in a distant part of the garden to-morrow. 
For I have found them filling the air with their cries along a particular 
stretch of jungle-road one day, whilst the next day not one was to be 
heard ; then perhaps, a week later they are back again in the same place. 
Living as they do in communities, they are constantly on the move, 
and from what we know of their great intelligence, it seems to me 
highly probable that their movements are guided by very definite plans, 
and that very probably they have some sort of government system. 
“In Cachar, where these notes are written, the tea-planters often 
keep Hoolocks for years, allowing them to run loose about the com- 
