16 



tilfældigt under disse Omgivelser, men maaske tør man 

 slutte, at denne Art, i Lighed med adskillige andre Dyb- 

 vandsformer. tilbringer de første Perioder af sit Liv i de 



øvre Vandlag. 



Yed en tidligere Lejliglied har jeg berørt 1 , at S. 

 marinus (ligesom S. viviparus) føder levende Unger, der i 

 Gydningsøjeblikket befinde sig omtrent paa samme lidet 

 udviklede Standpunkt, som det allerede gjennem Krøyer 

 har været bekjendt hos den sidstnævnte. mindre Art 2 . Yn- 

 gelens Totallængde i udstrakt Stilling hos 8. war /nu» er i 

 Gydningsøjeblikket omtrent 6"""; de ere dog strax istand 

 til at svømme om. og fore et selvstændigt Liv. 



Yngletiden falder ved de norske Kyster i Yaarmaane- 

 derne. i Eegelen fra Midten af April. til Midten af Maj, 

 medens 8. viviparus neppe normalt yngler for i Juli eller 

 August. Dog erholdes ogsaa af S. marina» gydefærdige 

 Exemplarer enduu langt ud paa Sommeren; under Gyd- 

 ningstiden tindes Individerne sjeldnere paa ringere Dyb, 

 end 100 Favne, men de fleste gyde sandsynligvis paa langt 

 større Dybder. Naar den gydefærdige Fisk faaes op i 

 Baaden. rinder ofte en Del af Yngelen ud af sig selv. og 

 flere Fiskere have iagttaget. at den levende Yngel svømmer, 

 livligt om i Våndet i Bunden af Baaden; det samme 

 kan man iagttage. om man opfanger den udrindende Yngel 

 i et Øsekar. 



Efter Gydningen maa saaledes Yngelen antages at 

 søge op i de højere Vandlag. og først naar de have naaet 

 en Længde af omkring 50— 60""". og faaet Farve og den 

 voxne Fisks almindelige rdseende. soge de atter ned paa 

 Dybet. 



Antallet af Rogn hos et noget større Individ (550""") 

 anslaar jeg til mellem 100,000 og 150.000 St. (Til Sam- 

 menligning kaii anføres, at jeg hos et Individ af 8. viviparus 

 med en Totall. af omtr. 300""" fandt blot omkr. 18— 20.000 St.) 



Hos de mindste af de under Expeditionen erholdte 

 Individer (fra Stat. 183). hvis Totall. var 9,r>"™, var hele 

 Legemets Dorsal- og Ventralside endnu omhyllet af Em- 

 brvonalhinden; Finuestraalerne vare alene i Caudalen tyde- 

 lige, men manglede i de øvrige Finner ; Ventralerne vare neppe 

 antydede. De 2 parallele Kamme paa Baghovedet vare 

 endnu ikke fremkomne, hvorimod Tænderne paa Præoper- 

 culum vare tycleligt afsatte. 



Hos andre fra samme Station, hvis Totall. var 12""", 

 vare Straalerne antydede i Pectoralen, ligesom Analens 

 Pigstraaler. medens Dorsalen endnu udgjør en sammenhæn- 

 gende Membran uden Straaler. Nakkekammen var nu ansat, 

 og endte bagtil med en dobbelt Torn. 



Hos det største Yngel-Individ (Stat. 248). hvis To- 

 tallængde var 19""". vare alle Finner og deres Straaler 



1 Forh. Vid. Selsk. ('bra. 1879, X<>. 1. p. 7. 



- Nogen Distinction mellem de '2 Former kan saaledes ikke hentes 

 fra dette Forhold, hvorfor Navnet viviparus ikke er synderligt be- 

 tegnende. 



and the species may. perhaps, in common with other deep- 

 sea forms, pass the earliest stages of its existence in the 

 upper strata of the sea. 



On a former occasion 1 I alluded to the fact, that S. 

 marinus as well as S. viviparus brings forth its young^ alive; 

 they are produced however at the same low stage of devel- 

 opment that Krøyer has already pointed out as characteri- 

 sing at birth those of the latter and smaller species.- 

 Total length of the fry of 8. marinus extended in a straight 

 line at moment of birth about 6"""; they are, however. 

 immediately able to swim and provide for themselves. 



Off the Norwegian coast the spawning-season is in the 

 spring months, and generally extends from the middle of April 

 to the middle of May ; S. inviparus, on the contrary, does not. 

 as a rule, produce its young earlier than July or August. 

 Examples of S. marinas with fully developed ova are. how- 

 ever, occasionally met with late in summer. During the 

 season in which they bring forth, individuals are seldom 

 taken at a depth less than 100 fathoms, the greater part 

 probably produce their young in far greater depths. When 

 a tish in that stage is taken, mature fry will frequently 

 drui) out; au£ l fishermen have observed fry swimming 

 friskly about in the water at the bottom of the boat, 

 which they will continue to do if transferred to a scoop 

 for examination. 



It thus appears that the fry of this . species rise 

 towards the surface shortly, or perhaps immediately, after 

 they are produced, choosing for their haunts the upper 

 strata of the sea. and do not descend to any considerable 

 depth till they have attained a length of about 50-— 60""" and 

 are of the colour, form, and general appearance of the adult tish. 

 The number of ova in a large, full-grown indi- 

 vidual (total length 550"'"'). may be computed at from 

 100.000 to 150,000 (in an example of 8. viviparus, total 

 length 300»"". I found only 18—20.000). 



In the smallest specimens of the fry obtained on the 

 Expedition (at station 183). total length 9.5""". the whole 

 of the dorsal and ventral margin was still enveloped in the 

 embryonic membrane ; the fin-rays were distinct in the caudal, 

 but wanting in the other fins; of the ventrals there was 

 hardly a rudiment; the two parallel combs on the occiput 

 were not yet developed, but the teeth on the preopercu- 

 lum were distinctly set. 



In other examples, taken at the same station, total 

 length 12™"', the rays of the pectorals and the spines of 

 anal were still rudimentary; the dorsal in this stage of 

 growth still constituted a. membranous flap without a trace 

 of rays ; the comb on the nape was now partially developed, 

 and terminated behind in a douple spine. 



The largest individual in the fry stage of growth (sta- 

 tion 248). total length 19»"". had all the fins and their 



1 Forh. Vid. Selsk. Chra. 1879, No. 1. p. 7. 



'- This circumstance cannot therefore be regarded as a specific dis- 

 tinction between the two forms, and hence the term viviparus does 

 not furnish a very appropriate designation. 



