THE PLANKTON 
477 
poses, will help to increase our knowledge of the relative 
abundance of the plankton over the oceans of the world 
and at different seasons of the year. Isolated observa- 
tions such as these may be of small value in themselves, 
but every expedition which collects such data thereby adds 
its quota to the gradually accumulating mass of evidence 
and brings the time for generalisation nearer to hand. A 
knowledge of the relative abundance of the food supply of 
the ocean is not only of scientific interest but of commercial 
importance. 
On the homeward voyage two satisfactory hauls with 
the trawl were obtained, one off the Falkland Islands in a 
depth of 125 fathoms, and the other off Rio de Janeiro in 
40 fathoms. The trawl scrapes the bottom of the sea, and 
brings up a fair sample of whatever animals and plants it 
can entrap or uproot. 
So little scientific trawling has been done in the 
Southern Hemisphere that almost every haul has a chance 
of containing some creature hitherto unknown from the 
area in which the catch was obtained. 
Animals which live at the bottom of the sea are known 
to zoologists as the benthos. 
During the outward voyage a day was spent on the 
island of South Trinidad by several members of the 
Expedition, and collections of land plants, land spiders, 
insects, and marine coastal animals were obtained. 
The collection of plants has been examined by 
Dr. O. Stapf of Kew Herbarium, and found to contain 
some thirteen species which have not hitherto been 
