DEALFISHES. 
309 
TKACH' YPTEROMORP S II. 
Body ribbon-shaped" , silvery and scaleless. Dorsal fin long ( extending along by far the greater part of the dorsal 
edge), in front high or crest-shaped and sometimes separated, into an anterior dorsal fin, which is deciduous and 
usually ivanting in old specimens. Anal fin small or wanting. Pectoral fins usually small , with few rays and. 
horizontal base. Ventral fins during youth long and f urnished with numerous rays, but entirely or (usually) partly 
disappearing 'with age b . Branches of the lower jaw high, and triangular. 
With the exception of the Cepolce, which are now 
referred to the Blennomorphs, Cuvier’s Tcenioides, as 
he eventually defined this family", corresponds to the 
Trachypteromorph series, which in Gunther is repre- 
sented by the two series Lophoti formes and Tceniiformes d . 
In many respects the Trachypteromorph series co- 
mes nearest the Mackerel series: the elongated, ribbon- 
shaped body, with the long dorsal fin, most nearly re- 
sembles that of the Trichiuridce, but also reminds us 
of the Dolphin-fishes ( Coryphcena ), the nakedness of the 
body too, reminds us most of the former, but also sug- 
gests the scaleless Horse Mackerels ( Gallichthys ), while 
its silvery, deciduous epidermis is a reminiscence of the 
Sea-Breams (Bramidce). The horizontal base of the pec- 
toral fins — which also occurs in the Trichiuridce — and 
the high, triangular branches of the lower jaw call to 
mind the Opah ( Lamp r is ). The history of development, 
which is always the safest guide to the determination of 
kinship, also seems to point in this direction, for what 
Ave now know, thanks to Emery’s valuable observations, 
of the development of the Trachypteroids, directs our 
special attention to the extraordinary reduction in the 
original length of the fin-rays, a point which had al- 
ready been shoivn in the species of the genus Gallich thys, 
starting from the Blepharoid stage, and, on a. smaller 
scale, in Selene , another genus of the same family. The 
round, black, lateral spots, which are so characteristic 
of the true Trachypteroids, as well as of the Dory, are 
also represented, strangely enough, by the evanescent 
spots in the fry of Gallichthys. These changes of de- 
velopment thus seem to indicate a starting-point common 
to the Scombromorph and Trachypteromorph series; but 
from this starting point their development has advanced 
in directions so Avidely different that Ave may Avell be 
justified in folloAving Gunther, and treating the latter 
series as independent. Anomalopterous characters, as 
Ave have already remarked, belong, as a rule, to the loAver 
(earlier) stages of development, and in the Trachyptero- 
morphs these characters have been retained in conjunc- 
tion Avith a most extraordinary shape of the body. 
The series contains two families, the one, Lophoti dee - , 
with only one genus, remarkable for the restriction of 
its occurrence, to the best of our knoAvledge, to the 
Mediterranean Sea and the Japanese part of the Pacific 
(see above, p. 69), and distinguished by the small 
size of the anal fin behind the vent, Avhich is situated 
close to the end of the tail, as Avell as by the slight 
degree of protrusion of Avhich the mouth is capable. 
The second family contains the true Dealtishes and the 
Oar-fishes (Kings-of-the-Herri ngs). 
Fam. t rachypte R I D m . 
Mouth capable of extensive protrusion. No anal fin. Vent situated at the middle of the ribbon-shaped body. No 
air-bladder. Pseudobranchice and pyloric appendages well- dev eloped. No branched or articulated fin rays". 
This family consists entirely of true deep-sea fishes, clusively from the solitary specimens which now and 
and our knoAvledge of its adult state is derived ex- then approach the surface for some reason or other, 
a This is the case in the museum-specimens preserved in spirits; but we know that, in these fishes, as in other true deep-sea forms, 
the body is of extremely loose structure, and shrinks considerably after death, while during life it is probably more terete. The fishermen 
of Finmark stated to Lili.jeborg in 1848 that the Dealfish he received from them, was “about 6 in. thick somewhat behind the head” just 
after its capture, i. e. at „this spot the thickness was more than half the depth. 
6 In Lophotes , however, the ventral fins are described as small, with the ordinary number of rays. 
c Cuv., Val., Hist. Nat. Poiss., vol. X, p. 309. 
d Acantliopterygii §§ III and IV, Syst. Syn., Cat. Brit. Mus., Fish.; Iutrod. Stud. Fish., pp. 519 and 520; Handb. Ichtli., pp. 369 and 370. 
e According to Kner (Stzber. Akad. Wiss., Wien, Math. Naturw. Cl., XXXIV, i (1859), p. 437, tab. 1), however, Tracliypterus al- 
tivelis, a Pacific species, is furnished with branched rays in the caudal fin. According to Costa ( Fn . Regn. Nap., Pesci, Acant. Scomberoidei, 
