194 THE DEPTHS OF THE SEA. [craP. IV. 
a mass of intermediate forms; and although after 
careful consideration I have described the two 
species as distinct, I find it a matter of great diffi- 
culty to draw the line between them. Several 
specimens of a handsome Astrogonium allied to 
A. granulare were taken on the ‘ Adventure’ 
Bank. Professor Duncan reports some interesting 
corals, and Professor Allman two new species of 
Aglaophenia ; and Dr. Carpenter detected once 
more the delicate Orbitolites tenuissimus, and the 
large nautiloid Litwola, with which he was familiar 
in the dredgings in the Atlantic. 
After a short stay at Malta, on September 20th the 
‘Porcupine’ steamed out of Valetta Harbour, and 
steered in a north-easterly direction, towards a point 
seventy miles distant, at which a depth of 1,700 
fathoms was marked on the chart. This was reached 
early the next morning, and the line ran out 1,748 
fathoms, lat. 36° 31’ 30” N., long. 15° 46’ 30” (No. 60), 
with a temperature of 13°4C., more than half a 
degree higher than the temperature of the deepest 
sounding in the western basin. The tube of the 
sounding apparatus brought up a sample of yellow 
clay, so like the bottom at some of the most unpro- 
ductive spots in the western Mediterranean, that 
it was not considered advisable to delay the time 
necessary for even a single cast of the dredge, which 
at that depth would have occupied nearly a day. 
Having thus satisfied themselves as far as they 
could by a few observations that the physical con- 
ditions of the eastern basin of the Mediterranean 
were similar to those of the western, they steered for 
the coast of Sicily. Quietly along the Sicilian coast 
