932 
SCANDINAVIAN FISHES. 
Sheppy Argentine , Penn., Brit. Zool. (ed. Warr. 1776), vol. 
Ill, p. 286, tab. LXV, No. 156. 
Salmo Miilleri, Gmel., Syst. Nat. Lin., ed. XIII, tom. I, p. 
1378; Kr. ( Maurolicus ), Danm. Fisk., vol. Ill, p. 113. 
Argentina Pennanti , Walb., Ichthyol. Art., pt. Ill {Gen. Pise.), 
p. 47 ; Cuv., Val. {Scopelns), Hist. Nat. Poiss., vol. XXII, 
p. 436; Yarr. (Richards.), Brit. Fish., ed. 3, vol. I, p. 
330; Day {Maurolicus), Fish. Gt. Brit., Irel ., vol. II, p. 49, 
tab. CIX, fig. 2; Colt,., N. Mag. Naturv. Clirnia, P>d. 29, p. 
104; Petersen, Vid. Meddel. Natnrh. For. Kbhvn 1884 (1886), 
p. 158; Lillj., Sv., Norg. Fna, Fisk., vol. Ill, p. 10. 
Scopelns borealis, Nilss., Prodr. Ichthyol. Scand., p. 20; Id., 
Observ. Ichthyol., p. 9; Id., Skand. Fna, Fisk., p. 479; 
Gthr ( Maurolicus ), Cat. Brit. Mus., Fish., vol. V, p. 389; 
Coll., Forli. Vid. Selsk. Chrnia 1874, Tillsegsh., p. 150; 
1879, No. 1, p. 84; Malm, Gbgs, Boh. Fna, p. 533; Winth., 
Naturh. Tidskr. Kbhvn, ser. 3, vol. XII, p. 42; Storm, Vid. 
Selsk. Skr. Trondlij. 1883, p. 30; Jord., Gilb., Bull. U. S. 
Nat. Mus., No. 16, p. 284. 
Scopelus Humboldtii , Yarr., Brit. Fish., ed. 1, vol. II, p. 94; 
ed. 2, vol. II, p. 161 (nec Risso, nec Cuvier); Storer, 
Mem. Amer. Acad. Arts. Sc., n. ser., vol. II, p. 450; vol. 
VI, p. 328, tab. XXV, fig. 5. 
Forma mediterranea (an species distincta?), maxillis et mandibula 
longioribus: 
Maurolicus amethystino-punctatus , Cocco, 1. c.; Gthr, 1. c., 
p. 390. 
Maurolicus australis , Hector, Trans., Proc. N. Zeal. Inst., vol. 
VII, p. 250, tab. XI, fig. 90, D, vide Gunther, Ann. Mag. 
Nat. Hist., ser. 4, vol. XVII (1876), p. 399. 
Obs. In 1766 Strom found on the shore, at Wolden parson- 
age in Sondmor, a specimen of this species (see his MS, quoted by 
Collett), a drawing and description of which lie sent ‘'more than 
20 years before 1791” (see Skr. Naturh. Selsk., Bd. 2, H. 2, p. 15) 
to O. F. Muller, who appends to his above-mentioned diagnosis, 
“Cl. StrOm misit.” Afterwards Strom confused this species with 
Myctophum glaciale, which he distinctly figured and described in 
Skr. Naturh. Selsk. (1. c.) — a circumstance first pointed out by 
Nilsson in his Skand. Fna. But this cannot affect the determination 
of Salmo Miilleri in Gmelin, who merely copied Muller. 
The Pearl-side belongs to the small fishes. Our 
largest specimen from Bohuslan indeed measures 72 
mm. from the tip of the lower jaw to the extreme end 
of the caudal fin; but the distance from the tip of the 
snout to the end of the middle caudal rays, the mea- 
surement termed in the present work the length of the 
body, is not quite 68 mm. 
The body is moderately elongated, with terete 
back and belly, flattened, vertical and parallel sides. 
In the forepart of the body, in front of the dorsal and 
ventral fins, the ventral contour is perceptibly more 
curved than the dorsal; but in the hind part of the 
body these contours are straighter and converge with 
fair uniformity towards the base of the caudal fin. 
The greatest, depth of the body, which occurs at about 
the middle of the preabdominal part, is about 1 / 5 (18 
— 2l7 2 %) of the length of the same"; and the least 
depth of the tail is about l / 3 of the said depth or 1 /. 15 
— Vie (about 6 V 2 % ) °f the length of the body*. The 
greatest thickness, which is fairly uniform throughout 
the forepart of the trunk (the preabdominal region), 
measures about 8 — 10 % of the length of the body. 
The outlines of the head run in uninterrupted 
continuation of those of the body, its sides being also 
flat and parallel; but the lower jaw, which sharply 
ascends when the mouth is closed, renders the inferior 
contour of the head more curved, while the superior 
contour is straighter. The forehead is also grooved 
longitudinally, its edges rising in a ridge that runs 
along each side, and extends forward above the margin 
of the eye, at the anterior upper angle of which it 
divides to enclose the nasal cavity; but the middle of 
the forehead is coursed by a lower longitudinal ridge. 
The length of the head is about 1 / 4 (26 — 22 1 / s %) of 
that of the body. The eyes are round, though their 
longitudinal diameter is somewhat greater than the 
vertical, and measures about 38 — 35 % c of the length 
of the head. They are set high, their upper margin 
lying almost in the plane of the forehead, and are only 
very slightly and obliquely upturned. The least inter- 
orbital width is about 2 / 5 of their longitudinal diameter, 
which is equal to the postorbital length of the head. 
The nostrils are set close together, each pair at the 
extreme front of the triangular nasal cavity, above the 
dark top of the preorbital bone and behind the arti- 
cular knob — also dark-coloured — of the maxillary. 
The anterior nostril on each side is round, the posterior 
an obliquely-set., transverse slit. The suborbital ring, 
which forms the silvery cheek, is thin but complete 
alon®- the lower half of the orbit, in front of uniform 
breadth, only slightly broader at the penultimate sub- 
orbital bone, the hindmost suborbital bone, on the 
other hand, being small and triangular. The tip of 
the snout is sharp (shallow) but truncate, with a slight 
indentation at the middle. The length of the slender 
intermaxillaries is equal to the vertical diameter of the 
eyes. The maxillaries are formed as in the preceding 
" 20 — 23 % of the length of the body excluding the caudal fin. 
b About 7 % (according to Lilljeborg nearer 8 /) of the length of the body excluding the caudal fin. 
c According to Liljeborg 32 % of the length of the head from the tip of the lower jaw. 
