106 



at Skjællene efterhaanden skulle beklæde et større Parti 

 af Legemet, end det. som Krøyer i sin Beskrivelse angiver, 

 idet kan ikke synes at kave iagttaget de fremspirende Skjæl 

 paa Halen. 



L. perspicillum er med andre Ord en spæd Unge, 

 som godt kan antages senere at ville forandre sin Farve- 

 tegning, ligesom den endnu ikke havde faaet sin folde 

 Skjælbeklædning. Da Legemsforholdene iøvrigt bos begge 

 ere overensstemmende, er det ikke usandsynligt. at i de 

 nærmest paafølgende Stadier af denne Forms Liv ville de 

 niorke Tverfelter efterhaanden lysne, og blive forandrede 

 til mindre Pletter eller reticulerede Linier, saaledes som 

 det netop viser sig hos det ovenfor omtalte unge grønland- 

 ske Individ af L. reticulatus med en Totallængde af 223""". 



Den næste i Rækken er L. ross/, opstillet af Malm- 

 gren i 1864 i Ofv. Kgl. Vet. Akad. Fork, eiter et Individ 

 fra Spitsbergen, erholdt under en af de første svenske Ex- 

 peditioner til denne Øgruppe. Dette Individ havde en To- 

 tallængde af blot 32""", og et Straaleantal af: D. 82. A. 

 63; i Farvetegning var det fuldkommen overensstemmende 

 med L. perspicillum, men Individet var. i Modsætning til 

 dette, helt nøgent. 



Det var. paa Grund af det sidstnævnte Forhold, at 

 Malmgren troede at burde opstille det som en distinct 

 Art, skilt fra L. perspicillum. Men da L. perspicillum. 

 som ovenfor nævnt, netop befandt sig i det Stadium, da 

 Skjællene vare i Frembrud, og Skjælbeklædningen endnu 

 ikke var fuldt udviklet, skjont det beskrevne Individ havde 

 en Totallængde af 65""", er det ikke uventet, at en spæd 

 Unge med en Totallængde af blot 32""", som L. rossi, 

 endnu intet Spor viser af nogen Skjælbeklædning. Ved 

 velvillig Imødekommen af Prof. Smitt har jeg erholdt tij 

 Undersøgelse dette Individ, og jeg kunde ingen væsentlig 

 Forskjel opdage mellem dette og L. perspicillum. 



Da endelig Prof. M. Sårs i 1866 i Christiania Viden- 

 skabs-Selskabs Fork, opstillede sin L. gracilis elter et i 

 Drobaksund i Christianiafjorden erholdt Individ med en 

 Totallængde af 43"""^ skeede dette alene af den Grund, at 

 hans Exemplar havde 10 mørke Tverfelter over Legemet, 

 medens L. rossi blot havde 8, og da fremdeles hans Exem- 

 plar var nøgent. ligesom L. rossi, kunde det ikke henføres 

 under L. perspicillum. Men allerede Krøyer har paavist, 

 at hans 2 Typ-Exempla.rer af L. perspicitlwm ingenlunde 

 vare fuldt overensstemmende i Tegningen af Kroppen; og 

 hvad Skjælbeklædningen angaar, gjælder det samme, som 

 ovenfor er anført under L. rossi. 



Dog maa paa dette Sted bemærkes, at Krøyers ene 

 Typ-Exemplar blot var 39""" langt (saaledes mindre, end 

 L. gracilis), og dog nævner han intet om. at der var nogen 

 Forskjel mellem de 2 Individer med Hensyn til Skjælbe- 

 klædningen; men selv om denne i Virkeligheden hos begge 1 

 har været lige, haves der Exempler paa. at dennes Udvik- 



1 Dette Forhold lader sig ikke længei plyse. IfølgeDr. Liitken 



er saavel det mindste Exemplar af L. perspiciUwm, som det eneste af 

 L. nebulosus ikke til at tinde paa Musæet i Kjobenhavn, og sandsyn- 

 ligvis ere de forsvundne. 



pectorals. Hence it is evident, that a larger part of the 

 body will gradually become scaled than is stated by Krøyer, 

 who does not appear to have observed these incipient 

 scales on the tail. 



L. perspiciUum is. in short, a very young individual, 

 in which a subsequent change of coloration may not un- 

 reasonably be assumed : as we have seen, the scaled inte- 

 gument had not yet attained its full development. The 

 proportions of the body being in all respects the same in 

 both, it does not appear un probable that, in the succeeding 

 stages of growth, the dark transverse patches will gradu- 

 ally become lighter, and change to smaller spots or reticular 

 lines, as is seen to be the case with the smallest Green- 

 land specimen of L. reticidabus, total length 223'"'". 



The next of the proposed forms is L. rossi, estab- 

 lished by Malmgren. in 1864 (Ofv. Kgl. Vet. Akad. Fork.), 

 from a specimen taken off Spitzbergen on one of the first 

 Swedish expeditions to that group of islands. This indiv- 

 idual had a length of only 32 M "'. the number of fin-rays 

 being: D. 82: A. 63; in coloration, it agreed precisely 

 with L. perspicillum, but differed from that form in being 

 naked. 



It was this feature which Malmgren deemed sufficient 

 to warrant his establishing it as a separate species. But 

 the specimen of L. perspicillwA, though with a total 

 length of 65""". having, as stated above, not yet reached 

 tke stage of growth in which the scales begin to form 

 (of some of the scales, indications had only just begun to 

 appear), it is not surprising that a very young indiv- 

 idual such as L. rossi. having a total length of only 32""". 

 should as yet be without the slightest trace of scales. On 

 application to Prof. Smitt, this individual was kindly lent 

 me for examination, but I failed to detect any essential 

 feature 'distinguishing it from L. perspiciUum. 



Finally, when Prof. M. Sars in 1866 (Christiania 

 Videnskabs Selskabs Forb.) described his L. gracilis, from 

 an individual with a total length of 43""". taken in Drøbak 

 Sound, in the Christiania Fjord, his sole reason for doing 

 so lay in the said example having 10 dark transverse 

 patches across the body, instead of 8, the number in 

 L. rossi: and his specimen being, like the latter, naked, 

 it could not be referred to L. perspicillum. But Kroyer 

 had already shown that his two typical specimens of L. 

 perspiciUum did not by any means exhibit perfect agree- 

 ment in the marking of the body ; and with regard to the 

 scaled integument, what has been said in connexion with 

 L. rossi, will apply with equal force here. 



The fact, however, must not be passed by. that one 

 of Kroyer's typical specimens was only 39""" long (accord- 

 ingly of smaller dimensions than L. gracilis): and yet no 

 mention whatever is made of any difference between the 

 two individuals as regards the scaled integument; but even 

 assuming it to have been the same in both, 1 instances 



1 Unfortunately, it is no longer possible to settle this question. Ac- 

 cording to Dr. Liitken. the smallest specimen of L. perspicillum and 

 the only one yet obtained of L. nebulosus, could not lie found in the 

 Copenhagen Museum, and are no doubt both ol' them lost. 



