9 
T. Y. HODGSON. 
Richardson. We were certainly unfortunate in not capturing a greater number of 
specimens. The small species belonging to the Janiridse, Munnidse and their 
allies were very abundant and much time was spent in going over the sponge 
debris, which was invariably the predominent feature in the shallow writer fauna; 
they were taken for the most part by the D - net inside the 25 - fathom 
line, and it is among these forms that the chief interest in the collection 
lies. Seven species, mostly assigned to new genera, have their eyes on enormous 
peduncles. This, I believe, to be an entirely new feature. In dealing with 
the Isopoda of the French Antarctic Expedition ( 12 ) Miss Richardson has introduced 
two species possessing this interesting feature to science; the ‘ Discovery ’ adds five 
more, and among those specimens the ocular peduncle is even more slender and 
elongated. Under these circumstances can the Isopoda be regarded as universally 
sessile-eyed ? Up to the present it has been so, and the Munnidse have been 
considered to be on the way to a different state of things. Among that family it is a 
very moot point whether the eye can be said to be on a peduncle at all, as the cephalic 
process is so large, but now these new southern forms show a long and slender peduncle 
quite on a par with those of the podophthahnous Crustacea, which reduces the value of 
a hitherto characteristic feature of this group to a minimum, and the existence of a 
joint has only to be proved to destroy it altogether. 
I here append a list, as far as I have been able to ascertain, of all Isopoda hitherto 
obtained in the Antarctic regions; several of these are as yet little more than mere 
names to me. Those taken by the ‘ Discovery ’ are marked with *. The total number 
is one hundred and eleven, of which twenty-nine belong exclusively to the Antarctic, 
seven more belong; to both the Arctic and sub-Antarctic regions, and the remaining- 
seventy-five exclusively to the latter. As stated in my Report on the ‘Discovery/ 
Pycnogonida, I take the northern limit of the sub-Antarctic region to be the mean 
annual isotherm of the surface water of 45° F., as defined by Buchan in the 
concluding volume of the ‘ Challenger’ Reports, and the latitude 60° S. as the boundary 
between the sub-Antarctic and the Antarctic regions proper. I have, however, gone a 
step further in dealing with some Pycnogonids from the Magellan Straits. I then 
found it desirable to define a Magellan region, and therefore divided the entire 
Antarctic into three provinces, naming them from their points of attack, it being- 
obvious that any visit to the South Polar regions would be made from the land masses 
to which these names refer, Kerguelen, of course, standing for Africa. 
In accordance with the above I have noted the province from which each species 
has been taken :— 
Australasian province between long. 100° E. and long. 130° W. 
Kerguelen province between long. 100° E. and long. 20° W. 
Magellan province between long. 20° W. and long. 130° W. 
It may reasonably be objected that these boundaries are purely artificial, and that 
