84 
is probably a distinct and undescribed species. It differs from MM. 
Cuvier and Valenciennes’ description of the Mediterranean fish, and 
from that by Risso of the same, under the name of Diana semilunata, 
in size, being only four instead of twelve or fifteen inches long; in 
proportions, the depth being contained three instead of not quite 
four times in the length, making it a deeper fish, and the length of 
the head equalling the depth; in having the eye exactly in, not partly 
before and altogether below the middle of the head, and the hinder 
nostril larger than the foremost ; in the less height backwards of the 
dorsal and anal fins, and their nearer approach at their hinder ends 
to the root of the caudal fin. The pectoral fins are longer, and the 
ventral fins, instead of being very short, with the first spine strong 
-and serrate, are half the length of the whole fish, with the first ray 
or spine feeble, weak, or slender, and perfectly even or entire ; the 
other rays, especially the first, being produced into fine hair-like 
points. The scales are firmly fixed, not easily removeable. There 
is no trace of the two little oblique crests or ridges at the base of the 
caudal fin on each side the faint central keel, like those which the 
Mackerels have ; and lastly, the pectoral and caudal fins, instead of a 
fine coral-red, are pale tawny or dirty yellowish white; the body 
being a dull silvery lead-colour, instead of silvery rose. 
It were not safe, from inspection of a single individual of such 
small size, and in a genus hitherto consisting of a single species, to 
pronounce these characters of actual specific value ; some, or perhaps 
all, may be due merely to age or sex. The name of A. plumbeum is 
therefore here proposed only provisionally for the Madeiran fish. 
Ausonia Cuvieri, Risso, Hist. ii. 342. f. 28; Cuv. Rég. Anim. ii. 214, 
note. 
Luvarus imperialis, (Raf.) Cuv. Rég. Anim. ii.214; Cuv. et Val.ix.412. 
I shall take an early opportunity in ‘The Fishes of Madeira’ of 
furnishing a full account, with a figure from a fresh and perfect in- 
dividual, of this little known, most rare, and interesting fish. The 
several discrepancies between my example, which is deposited in the 
Society’s collection, and the former individuals on record, seem fairly 
attributable to the paucity of those before examined, or to imperfect 
means of observation. ‘The Madeiran fish differs not more from each 
of those included in the above references than they do respectively 
from one another, whilst it presents an assemblage of characters 
only to be collected from them all. 
This really fine and striking fish offers no ambiguities whatever 
of affinity, the very fishermen regarding it as some kind of ‘‘ Dourado” 
(Coryphena), which it resembles, both in general aspect and in the 
form of the head and profile. Something about the mouth and pro- 
file reminds one also of the turbot, whilst in the shape of the body, 
and perhaps of the dorsal and the anal fins, it resembles the “ En- 
xareo” (Caranx luna, Geoffr.). The colour of the fins recalls to mind 
the Lampris. 
The length of this example was five-eighths of an inch less than 
three feet. 
