o 26 
THE VOYAGE OF H.M.S. CHALLENGER. 
“ The genus of long-legged prawns to which A. Milne-Ed wards has given the name 
of Nematoccircinus was frequently taken in the trawl when let down to great depths, and 
has a very extended geographical range. There are specimens from the following 
localities, the depths being the greatest reached by the trawl or dredge : — off the western 
and northwestern coast of Celebes Island, 255 to 2150 fathoms ; off Japan, 350, 560, 
1875, and 3000 fathoms ; near the Island of Juan Fernandez, 1375 and 1450 fathoms ; 
in the Southern Ocean, 1260 fathoms; off the Kermadec and Fiji Islands, in 600 
fathoms. 
“ The fact that the depths vary from 255 to 3000 fathoms suggests that the animals 
do not live at the greatest depths reached by the nets, but that they are caught while 
swimming in mid-water and brought to the surface. Two Stations with the greatest 
depths are not far distant from two or three of the shallower ones, hence in the same 
regions the species have either the power of living under very different conditions of 
temperature and bathymetrical influences, or they live suspended in the ocean over the 
greater depths. The several species brought home vary in points of little importance 
from each other, such as a longer or shorter rostrum, a shorter or a longer foot. They 
extend from the Polar regions to the Equator. 
“ One of the most abundant of specific forms is that of the genus Alphceus, in which 
I include those congeners that have been separated from it, more for the convenience of 
classification than on account of any structural value. It contains twenty recognised 
species, which with a single exception have been taken within a depth of 50 
fathoms. They are mostly recorded from muddy bottoms, but they are also frequently 
found sheltered among masses of Sponge or Coral. I am induced, from the peculiar 
localities in which they are found, and the protected condition of their eyes, to believe 
that they burrow beneath the surface of the mud. They are mostly inhabitants of the 
warm seas, abounding in tropical and subtropical regions, becoming more scarce in the 
temperate, and gradually disappearing towards the cold temperate and Arctic regions. 
One species, Betceus truncatus, is recorded from Cape Horn, where it was dredged in 
about 10 fathoms. With this exception none has been observed farther south than 
New Zealand or 50° S. lat., or farther north than the English Channel or 50° N. lat. 
They are essentially a sublittoral form, for the instances of their having been taken 
in depths greater than 20 fathoms are few. Alphceus avcirus in the Challenger collection 
is recorded as having been twice taken off the coast of Australia, once at a depth of 
8 fathoms, and once when the dredge had been sent down to 2675 fathoms. 
“ The members of the Penseid division exist most numerously in the open waters of 
the ocean, some genera passing their whole existence within 100 fathoms of the surface ; 
others are found as constantly in deep water below 300 fathoms, while others again 
appear to exist in the more remote abysses of the deepest parts of the ocean in close 
contact with the sea bottom. 
