42 6 



SCANDINAVIAN FISHES. 



iiietry shown ])\- other fishes than the retiiaiiiing mem- 

 bers of tlie family. The present subfamily shows the 

 least degree of asymmetry in the structure of the mouth, 

 but, on the other hand, has advanced furthest in the 

 asvmmetr)- of the tins. The ventral fins, in the first 

 l)lace, ai-e I'cnioved towards the blind side so far tliat 

 the ventral fin of the eye side acquires the appearance 

 of an anterior anal fin, a peculiarity Avhich also occurs 

 in some of the members of the subfamily of the Soles. 

 But, in addition to this, the posterior parts of the dorsal 

 and anal fins are generally drawn over towards the 

 lilind side so far that their terminations on this side 

 are closelv ajiproximated to each other in front of the 

 caudal fin. In the position of the eyes too, some of 

 these forms (a pai-t of tiie genus Plaf(ipl/r//s) attain the 

 highest degree of asymmetry, the -wandering eye finally 

 taking its place so far back and so higii up that it 

 seems externally to belong to the occipital region. The 

 direction of the asymmetiy in this subfamily may thus 

 l)e said to be opposite to the direction of fliat which 

 determines the structure of the Soles. 



Among the peculiarities of the skeleton the struc- 

 ture of the pelvic bones first calls for attention. These 

 bones are partly — in Bothus yhomhiis for example — 

 of the same shape and position as in the symmetrical 

 fishes, Avitii tlie exception of the circumstance that they 

 liang downwards from tlieir point of suspension from 

 the clavicular bones. Thev are stiletto-like, of an ol)- 

 long triangular shape, at the superior (originally the 

 anterioi') end cui'ved and tubular, with the narrow side 

 (the base) set transversely across the liody; and in the 

 species mentioned the outer exterior corner forms a 

 spinous process. But eacli of these bones sends out, in 

 a forward direction, from the lower part of the outer 

 side, a, thin, narrow, triangular, osseous disk (pointed 

 in front), which is set verticallv in the longitudinal 

 direction of tlie body (horizontally when the bod)- is 

 in its usual position), and whicli follows the ventral 

 margin, under the posterior (lower), for\\ard prong of 

 tlie urohyoid (basibranchiostegal) bone, but is united 

 to tliis bone solely by ligaments. The outer surface of 

 this osseous disk represents the upper (posterior or 

 inner) surface, and its anterior point the hind (lower), 

 exterior corner, of tiie jxdvic bones of ordinary fishes. 



The six ventral rays, ^\■hich are more or less apart from 

 each other, articulate with the under surface of this 

 disk, their outer side tims corresponding to the upper 

 (inner) side of the rays of the ventral fins in ordinary 

 fishes. Another peculiarity wiiicii distinguishes the ske- 

 leton of these fishes from that of the preceding sub- 

 family, is that the caudal vertebra;' are furnished with 

 comparatively well-developed transverse processes. 



A characteristic of most of these forms — though 

 it also occurs in the preceding subfamily, in the genus 

 Pseudorliomhus for example — lies in the shape of the 

 pupil. On its inner side (in the lower eye the upper 

 side, in the upper eye the lower) the iris forms a semi- 

 circular or (piadrangular process, which tluis hides a 

 part of the [tupil. 



Almost all tliese forms — the genera Mai/copsrtfa 

 (from the Indian Ocean off Prince Edward Island), 

 CifJianis (from the Mediterranean), Cifliayichflu/s" (from 

 the tropical parts of the Atlantic, Australia, and the 

 west coast of North America), Platophrijs'' (from the 

 Temperate and Tropical seas all round the world). 

 Bothiis, Lepldoihombus, and Scopthahnus (from the At- 

 lantic and the Mediterranean), as well as Zeugopterus 

 (from the Atlantic coast of north-western Europe) - — 

 are sinistral. Onlv the ('hinese genus Saniaris, which 

 is I'emarkable in many other respects, has the eyes on 

 the right side of the body'. The vent usually lies on 

 the blind side, but tiie anal papilla in most cases on 

 the eve side, and often even aljove the ventral fin of 

 this side. In all tliese forms the dorsal fin begins in 

 front of the eves, on the bridge of the snout or the 

 blind side thereof. 



The forms of this subfamily that belong to the 

 Scandinavian fauna ma^- lie distinguished as follows: 



A: Jaw-teetli set in !i single or 



double row. fjrancliiostcgal 



membranes united inferiorh' 



in n straigiit line witfi each 



otlicr. 



(jenus Plalophri/t<: Jaw-teeth 

 of uniform size (no ca- 

 nines); vomer toothless. 



Subo-enus Arnoglossut:: Sea- 

 les middle-sized and do- 



ciduon s _ Platophri/s ( A rn ofilossiis) la ternn. 



B: Jaw-teeth set in several rows, 



cardiform. Branchiostogal 



" -|- //ciiiirliomljiifs -t- Anticitliarns. 

 '' -I- Ariior/lnsitiis. 



"^ According to GCntheh's descriiilioii the eyes are sol, on (lie left side of tiie liody in Loii/ionectcs, from Port Jackson: but according 

 tci Ids fio-urc (liis 2:pnns is dextral. 



