Knii.ll DAIi. 



4-2;^. 



wliilr uiily female (.•luira(;lcrs aru niveii in tin.- oilier Iwn. If wu 

 iliiiiiiKiti' llii.s (lislurbiiig iiilliieiioe from the Cduiiiurison, Ur' rcsull 

 becomes still ekvirer: Drepiuwp.ieUa jilntessoide.f represeiilK the liigliest 

 stiigv of ilevelopiiK'iit (if tlie femali' rliararterK. 



If we now compare this table «i(li tliat ^iveii above (p. 407), 

 wliirh shows the rehitioii between the fuiir forms of the I'laiec f^froiip, 

 we liiul that, ill \'l of llii' III relations there i;'i\en, as soon as the 

 percentage is greater in I'leiiv. ijluviali.-f than in Pleiir. cicatrii:osiis, 

 or when the percentage is greater in Flenr. jdatensa (ban in Pleitr. 

 jitsiis, the |ierceiitage in l>n:piiiioii.t':tt(i jildte.'t.ioiile.i is also grenler 

 than ill Ih-i-jxiii. limaiidoiiles, while, when the percentages run in the 

 miposiie direction, the case is reverscil. Again, just as I'teiironectes 

 ijlat'ialis is a more strictly .\rctic form llian I'lciw. cii-ntn'i.-fl.tn.f, so 

 also Dvcpdnopnetta platcf'Soidcs, as being a (jrcenlaiul form the soiith- 

 waril range of which is boinuled by the soutliern tcrmiuatioii of tin- 

 Arctic current that folluws the cast coast of Nortli Aiiirrica. may be 

 regarileil as a more Arctic form than Drepaiiopiif'tta limiiuitoi<li!S, which, 

 it is true, goes as far north as Spitzliergcn, but is also found at least 

 as far soiilli as the south-west point of Knglaiid, where no ciirrcnl 

 can explain the occurrence of Arctic forms. Thus, the original form 

 of this group, too, has probably belonged to the Arctic fauna. 



With these reservations, and until a more e\lensi\e supp|ily of 

 materials for e.\aniiiiation may perhaps put this ([iiestion in another 

 light, we adopt the opinion first hazarded by lii'NTilKii and snbse- 

 ipieiilly more deliberately weighed by tJoi.i,i;'rr, that holli these forms 

 may be included under a common specific name. Among tlie syn- 

 onyms of the species Brown-Goopk and Ukan also give Stohkr's 

 Flfile.<.t,( ilciitatii, though lie stales (Mem. Amer. Acad. Arts., Sci., 

 u. ser.. vol. V'lII, part. II, p. .'!'.) 1) that in its case the dorsal fin 

 bea'iiis jiii<t ocer the middle of the e//e, an expression which, if we 

 ailopt the synonym, must not be taken too liler.-illy. 



( )ii the cuast uf Sc;iii(liii;i\ i;i the .-iv cftige length of 

 flic Koiigli Dal) is 22 — 25 cui., tlidiioii it is sometimes 

 29 — ?>'! Ill' t'\"eii .")") cm." long. .\|i;irt tVom its Ini'ge 

 iiioiitli, llic species shows ;i general fcsctiililancc to the 

 l>al) ( /'/. l/iixti/iht): nnd it is tVom this that the name 

 of Ihiiiiiiiliiides is deviveil. in the torni which occiifs in 

 .Se;inilina\ian watei's the gi-catcst ilcjitli of the IkhIv is 

 ahotit ' .; of the total length, and the greate.st tiiickness 

 ahotit ' I of the greatest tleptli. 'I'lie length of the head 

 measiifcs ahotit ' , (2() "'.) of the length of the liody 

 lo the base of the caudal tin. TIk' dorsal ftl'^r of the 

 head slopes evenh' downwai'ds fi-oin the heginning ot 

 the hack. The eves ai'e e\actl\" the same in fofiii and 

 .stfiictiifc as ill most of the I'doiinders; they ai'c almost 

 ei|iial in size and afe set on the i-iglit side, the nppei- 

 seafcei\- ', - of its length hehind the lower, 'i'lie length 

 of the lattei' is in \onng specimens somewhat gTeater 

 than, in old ahoiit eipial to, the distance between it 

 and the 1i]i of the snoiit: and its hind margin lies at 

 idtoiit the end of the second fifth of the head. The 

 inner side of etich eve (the side nearest the othef eye) 

 is .soniewhat mofe raised than in most flat fishes, the 



" On the English coast, according to I).\v, a specimen :'.8 cm. 

 '' For the function of these folds, see above, p. -jri:!. 



pMsiiioii III' the iris being thus moi-e ncai'K' \(,Ttical, and 



llie pupils beiliL!- Ilinied ill o|ipi)^ile (li n -el i( ills. Tills i.s 



it similaf .■in'angement to that which en.-ibies the hlat- 

 fishes in general to see botli to the right side and the left 

 without an\' special (;.\ertion, when tlie\' are King with 

 ihe liliiid side oil the iiottoiii, and which is supple- 

 mented h\' the great iiiobilit\- of the e\cs. in tills 

 species the iiiterorbitMJ space forms a narrow cariiiii, 

 soniewhat higher than usual, which, in spile of this, 

 disappears as we follow if back\\ards. The nostrils of 

 each pair are distincth' separated from each other. On 

 the e\e side the anterior nostril, which is obliipieh' 

 raised into a tubular foian, lies just at the eilge nf the 

 cheek-fold (the lower margin of the pr(.'ori)ital bijiie) 

 abo\e the nia\illar\ bone, while the posterior, wliieli 

 is without raised margin, is situated somi-wliat higher 

 up tliiin the anterior, almost in the line drawn between 

 the anterior margins of the e\es, but nearer to the 

 lower e\-e tliaii to the u|ii)er. The nostriK of the blind 

 side, wiiicli in other respects resemble those of the eve 

 side, lie somewliat nearer each other, in a .stniight line 

 with the base of the dorsal tin, tlie anterior beiuff situ- 

 ated about half-wa\" between the lower margin of the 

 preorbital fild aii<l the beginning of the dorsal fin, or 

 somewhat nearer tlie former. The mouth is fairly large, 

 this heing the most striking ditt'erence between this 

 species ;ind the true Flounders: and the upper jaw -bone 

 is so long tliat, if bent upwards abo\e the lower eye, 

 it would extend to the hind margin of the latter. The 

 teeth are conical and pointed, especially on the iiiter- 

 maxillarx Iioik-s: small, but in front, espeeially on the 

 interma\illar\ bone of the eye side, larger; and ar- 

 ranged in a single, rather irregular row, at intervals 

 about ei|ual to the breadth of ;i tooth. < )n the eve side 

 the\- are recurved ami behind smaller, but are present 

 aloiio' both jaws, except in the hindinosl jiart of the 

 lower jaw. Ill this species as in most of the hlatti^hes, 

 the twd transver.se dermal folds ([)alatal curtains) within 

 the rows of teeth, both in the ii|iper jaw and the lower. 

 ,ire broad and resemble true vela''. The gill-cover is 

 free, its usual, above the pectoral tin ami across the 

 posterior opercidar corner. Tlie margin of tlie hrau- 

 chiostegal meiiibrane is not folded back so far as in most 

 of the .'Scandinavian Flattishes. This i- the only .'^candi- 

 mniaii species of the I'hiiinder-series tliat has s braii- 

 chiostegal ra\s, 7 lari;e and somewhat flattened rays on 



long lias been foinid. 



