ANCHOVY. 
993 
geners. The ethmoidal region is prolongated in front 
of the mouth and above the intermaxillaries, which 
are even more reduced than in the preceding Clu- 
peoid forms. 
The head in its remaining form and structure 
lends itself most readily to a comparison with that of 
the Greater Scopelus ( Myctophum elongatum). This 
resemblance may be seen in the large, horizontal cleft 
of the mouth, with the gill-slits extending far forward 
in the lower jaw, the very strongly constricted cheek- 
region below the eyes, and the backward and down- 
ward prolongation of the opercular apparatus, the pre- 
operculum having lost the lower, horizontal arm that else 
projects in a forward direction. The cheek behind the 
eye is also of the same triangular form as in the said 
Scopeloid. 
In Anchovies 13 — 15 cm. long the length of the 
head occupies about 21 V 2 — 227 8 % °f that, of the body. 
So great, however, is the extension of the pharyngeal 
and opercular apparatus that the head itself, from the 
tip of the snout to the occiput, measures only about 
V 7 of the above length. The longitudinal diameter of 
the eyes, which are round, but incline to an oval shape, 
is between 24 and 2 1 1 / 2 %, their vertical diameter about 
20 %, of the length of the head. The eyes and the 
sides of the snout in front of them are covered by an 
adipose membrane, which is quite continuous, without 
aperture or eyelid, but transparent on the pupil. The 
interorbital width at the middle of the eyes is slightly 
greater than their vertical diameter, but less than the 
longitudinal. The length of the snout is slightly less 
than the said vertical diameter, the difference being 
least in old specimens. The nostrils on each side are 
set close together, being divided only by a narrow 
strip of skin, which may, however, be elevated so as 
to form an obliquely cut groove, open in front. They 
are set at the edge between the flat or faintly convex 
top of the snout and its converging sides, about half- 
way between the tip of the snout and the anterior 
margin of the eyes or a little nearer to the latter. 
The small, stiletto-shaped, and curved intermaxillaries 
are attached to the lower anterior margin of the long 
maxillaries. The latter bones increase uniformly, but 
slightly, in breadth behind, where each of them is fur- 
nished with two narrow jugal bones, pointed in front, 
a On the sides of the head of the vomer, on the palatines, 
ectopterygoids. 
their greatest breadth, including the jugal bones, being- 
only about 7 10 of their length. The lower jaw is also 
shallow and long, in contradistinction to that of the 
preceding Clupeoids; it is slightly turned up at the 
tip. The length of the maxillaries is about 61 — -65 %, 
that of the lower jaw about 68 — 71 %, of the length of 
the head. The intermaxillaries, maxillaries, and lower 
jaw are each furnished with a row of small pointed 
teeth, somewhat curved and of uniform size. Similar 
teeth may be found on almost all the bones of the pa- 
late", but are more or less deciduous. In old specimens 
the teeth of the maxillaries, and sometimes, at least in 
part, those of the lower jaw, also disappear. The tongue 
is small, cartilaginous, and toothless, but free. Close 
to its base begins the fine denticulation of the long and 
narrow row of copular bones. Both the upper and 
lower pharyngeals are armed with small teeth. The 
gill-rakers are long and fine, numbering about 62 — 72 
on the first branchial arch. 
The top of the head, which is almost flat, is coursed 
at the middle by a longitudinal ridge from the very tip 
of the snout (the upper margin of the ethmoid bone) 
to the occiput; and from the inner side of each pair of 
nostrils, obliquely outwards to each supraorbital mar- 
gin, and thence obliquely inwards to the occiput, there 
run the same ridges as in the Clupeoid forms im- 
mediately preceding the Anchovy. The cephalic sy- 
stem of the lateral line is generally less developed than 
in the said forms, but here too varies considerably in 
its development. In some instances only faint traces 
thereof appear; in others the whole top of the head, 
the temples, the upper parts of the scapular region, and 
the triangular cheeks are covered with numerous, ver- 
rucose elevations and pores, sometimes with a network 
of confluent ducts belonging to this system, and the 
hind margins of the operculum, the preoperculum, and 
the scales on the scapular region are pierced by the 
straight, backward ramifications of these ducts. The 
preoperculum is crescent-shaped, though the lower cor- 
ner is somewhat prolongated, forming a thin, rounded 
lobe. The operculum is quadrangular and of uniform 
breadth, but curved like a sickle, its upper anterior 
margin, above the articular head, being perpendicular, 
and its whole posterior margin forming a fairly regular 
curve of about a quarter of a circle. Its lower posterior 
on the entopterygoids. and, in a small card, on the hind part of the 
