30 NOTES OF A BOTANIST 
prickles, capable of sustaining very heavy weights. 
Both these lianas grow chiefly on the banks of 
rivers, and are a serious impediment to navigation 
where the current is strong and canoes must 
necessarily creep up close inshore. On the rivers 
entering the Gulf of Guayaquil the Uncaria is still 
more abundant than at Para, and there have been 
instances of a man being caught up by its for- 
midable hooks and suspended in mid-air, whilst 
the raft on which he was shooting down the stream 
floated away from under him. But of all river-side 
lianas, the most to be dreaded are the Yacitara 
twining palms of the genus Desmoncus, the ter- 
minal pinnae of whose leaves are abbreviated to 
rigid spines pointing backwards like the barb of an 
arrow. As the canoe shoots by or under an over- 
hanging mass of Yacitara, woe to the unlucky 
wight who is caught by its claws, which infallibly 
tear out the piece they lay hold on, whether it be 
flesh or garment, or both. 
In the virgin forest one not infrequently sees a 
plant curiously flattened to the trunks of trees, and 
at a distance looking more as if it were painted 
than as if it grew thereon. The leaves are from 
I to 3 inches long, closely and symmetrically 
set on to the stem in two rows, oval, with a 
rounded apex and a heart-shaped base, of a deep 
velvety green beautifully netted with the white 
veins. It is the young state of Marcgraavia um- 
bellata, and is so totally unlike the mature state, 
that it was only by actually tracing the union of the 
two forms I could satisfy myself of their identity. 
The stem puts forth here and there clasping roots, 
which adhere to the tree, or even completely em- 
