46 
ICHTHYOLOGY 
anal of a reddish pink ; the end of the caudal and of the 
prolonged rays of the dorsal black ; ventrals also of that 
colour. 
When the mouth is fully extended, the distance from the 
anterior end of the jaws to the front margin of the eye, is 
equal to the one from this same margin to the base of the 
dorsal. 
The first dorsal has eight rays, or rather one spine and 
seven rays ; the second, thirty rays ; the anal has two spines 
and thirty rays ; the ventrals one spine and six rays ; the 
pectorals eleven rays. 
The height of the body is contained once and eight-tenths 
in the total length of the fish • the head is twice and one- 
third in the same, the eye is contained three times in the 
head. 
This sort seems to attain considerable dimensions, as I have 
a dried specimen, which with its mouth extended has sixteen 
inches in length, and its breadth is over six. 
TRACHURUS TRACHURUS. 
Scomber Trachurus, Lin. Syst. Nat., vol, i., p. 494. 
This genus has been formed on the horse-mackerel, and it 
is only very lately that I have been able to observe it on the 
the Melbourne market. Specimens of this fish are found 
almost all over the world, and are so very similar one to the 
other as to make it probable that they all belong to one sort. 
They present, it is true, some variations in the number of the 
shields which form their lateral line, and also in the form of 
this line itself. The numerous specimens I observed at the 
Cape of Good Hope seemed to differ enough from those of 
Europe to justify their specific separation from them {Track. 
Capensis, Cast.); but sorts founded on such slight characters 
are always very doubtful, and will only be well established 
when numerous specimens from all parts have been carefully 
compared. 
The two specimens I have seen at Melbourne have their 
height contained four times and two-thirds in the length, up 
