122 



SCANDINAVIAN FISHES. 



(^eive the cartilage which connects them with the pos- 

 terior rays of the pectoral tins. Another peculiarity 

 in the skeleton of the Opah whicli seems to indicate 

 a lower (older) degree of development, appears in 

 the structure of tlie last caudal vertelarje. The last 

 of all, as usual, is without any true haraal arch; 

 but the three next to it have theii- hannal arches free 

 a,nd not united to the bodies of the vertebrae, and the 

 vertebra next in front of these has the htxMnal arch 

 united to its body, but retains the suture between them. 

 Tlie penultimate vertebra has both hannapophyses wi- 

 dened at the base into a projecting ridge, which runs 

 along the loAver posterior part of the vertebra on each 

 side, and is continued backward across the hypural 

 bones, where it is free. We have above remarked a 

 I'idge corresponding to this in the common ^lackerel, 

 where it does indeed belong apparently to the hypural 

 bones (the last caudal vertebra), thougli, there too, it 

 originates distinctly on the side of the penultimate 

 caudal vertebra. Even in tlie skeleton of the adult 

 Mackerel and of the Scad, too, we may trace in tlie 

 last caudal vertebrae (as far as the fourth from tlic 

 end) sutures reminding us that the ha^inapophyses 

 were free in the earlier stages of development. Thus 

 the skeleton of the Opah, even Avhen the body is 1 1 

 dm. in length, explains a circumstance the elucidation 

 of wliicli in the Mackerels must probablj' be sought 

 in the youngest specimens. 



The fauiily Lampriclidce thus possesses points of 

 resemblance to all the preceding families in the long 

 Mackerel-series — to the Bramoids in the high form 

 of the body, to the Carangoids in the liigh supraocci- 

 pital crest, to the Scombroids in the large number of 

 the vertebrte and to the Xipliioids in tlie reduction of 

 the ja^v-teeth and the circular form of the nostrils. 

 But in this family we also find anomalopterous cha- 

 racters liotli in the situation of and in the number of 

 rays in the ventral tins — the nunil)ei- of tlie rays 

 calling to mind the position of Benjx in the Perch- 

 series — as well as in the articulation of the pectoral 

 fins. In the formation of the gill-covering ajiparatus 

 it most nearly resembles the Carangoids, though the sub- 

 operculum is considerably smaller, and shaped like a 

 triangular lamina, which occupies only a tiny part ot 

 the lower corner of the margin of the gill-opening. 



As our knowledge of the changes of growth in 

 the family is so imperfect — we onl}' know that the 

 tips of the dorsal and ventral tins become shorter with 

 age" — and especially as the younger stages and the 

 supposed larval stage are completely unknown, we have 

 no data of sufficient importance to decide the correct 

 place of the family. Its ^vhole appearance, however, 

 speaks in favour of its retention within the Mackerel- 

 series, although the anomalopterous characters just 

 mentioned may seem to assign it another place in the 

 system. 



Genus LAMPRIS', 



The only genus within the family, contains only one known species, 



" Cuv., Val., Hist. Nat. Poiss., vol. X. p. 58, tab. 282; cf. also Cuv. (Val.), Regn. Anim. Illustre, Fois.'-'., pi. Gl. 

 '■ Ketzil'S, Vet.-Aka.l. Handl. 1799, pt. 2, p. 91. 



