8 



der sidder fast ved en kort og tynd Stilk, for tilsidst sand- 

 synlig at løsrive sig og falde ud i Vandet. 



Medusegemmernes 4 Randtentakler (d) vare i Bege- 

 len rudimentære, knop- eller lidt kølleformige og alle af 

 samme Størrelse; kun hos en eneste Gemme (Fig. 12) 

 bemærkedes den ene Tentakel (d') allerede at have for- 

 længet sig betydeligt, idet den havde antaget en traad- 

 dannet d. e. ved Basis tykkere og imod Spidsen efter- 

 haanden tyndere Form. Umbrella viste hos alle større 

 Gemmer livlige Bevægelser af Systole og Diastole, og 

 naar en af dem kunstig afløstes, svømmede den en Tid 

 lang frit omkring i Vandet paa Medusernes sædvanlige 

 Vis. Undertiden, især naar Gemmerne vare nærved at 

 dø, trak Umbrella sig stærkt sammen i Længderetning, 

 hvorved Manubrium traadte mere frem (indtil Halvdelen 

 af dens Længde) udenfor Aabningen af samme. Kappen 

 var aldeles farveløs og vandklar; paa Subumbrella bemær- 

 kedes, især under Systolen, talrige overmaade fine para- 

 le]le Tværstriber, udentvivl Muskelfibre. Manubrium var 

 indvendig, d. e. i dens Hulhed, lys gulagtig (straagul), 

 Tentakelrudimenterne bleg rødlige. Paa den forsmalede, 

 et kort Rør lignende Ende af Manubrium (h) syntes der 

 allerede at være en cirkelformig Aabning, Munden. I 

 Diaphragma eller den tynde ringdannede Hud ved Aab- 

 ningen af Kappen (g) bemærkedes radiære Muskelfibre. 

 Denne Hud slaaes ved Diastole udenfor og ved Systole 

 indenfor Aabningen af Kappen. 



Skjøndt man ifølge disse Iagttagelser vel kunde nære 

 nogen Tvivl, om Medusegemmerne hos C. Sarsii nogen- 

 sinde løsrive sig, da de allerede medens de ere fæstede 

 til Moderdyret producere Æg og Sperma, synes dog paa 

 den anden Side deres fuldstændig meduselignende Bygning 

 heller at tale for, at de dog virkelig tilsidst løsrive sig 

 fra Moderdyret og blive til frie Meduser. I saa Tilfælde 

 synes de imidlertid ikke saaledes som Gemmerne af fore- 

 gaaende Art at udvikle sig til nogen Art af Slægten Steen- 

 strupia, men heller til en Art Sarsia, Oceania eller en 

 anden lignende med ligelig udviklede Randtraade forsynet 

 Slægt af de lavere Meduser. 



3. COBYMOBPHA ANNÜLICOBN1S, M. Sars. 



(Tab. 1, Fig. 17—3.) 

 Sars, Christ. Vid. Selsk. Forhandl., 1859, pag. 99. 

 Denne lille, meget distincte Form, som jeg ikke uden 

 nogen Tvivl henfører til Corymorphaslægten, fandt jeg for 

 mange Aar siden (i Juni 1836) ved Florøen i Søndfjord, 

 Bergens Stift, paa 30—40 F. D., dyndet Grund, i 2 Exem- 

 plarer. 



Jeg har saalænge udsat med Bekjendtgj øreisen af den 

 Beskrivelse, jeg da udkastede og som vistnok lader meget 



and more concentrated, becoming at last globular with a 

 smooth surface ; at the same time it begins to raise itself 

 over the surface of the manubrium, like a berry attached 

 by a short and thin stem, whence it finally detaches itself 

 and falls off in the water. 



The 4 marginal tentacles (d) of the gonozooids were 

 as a rule, rudimentary, bud-like or somewhat claviform, 

 and all of the same size; only in one single gonozooid 

 (fig. 12) the one tentacle (d) was observed already to 

 have elongated itself considerably, having assumed a 

 thread-like form thicker at the base, and gradually thinner 

 towards the extremity. The umbrella in all the larger 

 gonozooids exhibited active movements of systole and dia- 

 stole and when one of them was artificially detached, it swam 

 freely about in the water for a long time, as the medusæ do 

 usually. Sometimes, especially when the gonozooids were 

 about to die, the umbrella contracted itself strongly in a 

 longitudinal direction, which caused the manubrium to 

 project further (until the half of its length) beyond the 

 aperture. The umbrella was quite colorless and pellucid; 

 on the sub-umbrella, especially during the systole, there 

 appeared numerous extremely fine parallel transverse 

 stripes, without doubt muscular fibres. The manubrium 

 was internally, that is in its cavity, of a light yellowish 

 (straw) color; the rudimentary tentacles pale reddish. On 

 the contracted end of the manubrium (A), which resembled 

 a short tube, there appeared to be already a circular 

 opening, the mouth. In the diaphragm, the thin annular 

 membrane at the aperture of the umbrella (g), radial 

 muscular fibres were observed. This membrane is in the 

 diastole thrown outwards, and in the systole drawn within 

 the aperture of the umbrella. 



Although, according to these observations, some doubt 

 might be entertained as to the gonozooids of the C. Sarsii 

 ever becoming detached, seeing that they already pro- 

 duce ova and sperm while still attached to the parent 

 animal, yet their complete and medusa-like structure seems 

 on the other hand to warrant the inference that they do 

 really at last detach themselves from the parent animal 

 and become free medusæ. In this case it does not how- 

 ever appear that, like the gonozooids of the preceding 

 species, they develop themselves to any species of the 

 genus Steenstrupia, but rather to a species of Sarsia, 

 Oceania or of some other similar genus of the lower me- 

 dusæ furnished with uniformly developed marginal fila- 

 ments. 



3. CORYMOBPHA ANNÜLIC0BNI8, M. S aes. 



(Tah. 1, fig. 7-13.) 

 Sars, Christ. Vid. Selsk. ForhandL, 1859, page 99. 

 Of this small very distinct form, — which, not with- 

 out some hesitation, I refer to the genus Corymorpha.— 

 I found the first 2 specimens many years ago (in June 

 1836) near Floröen at Söndfjord in the province of Bergen, 

 at the depth of 30—40 fathoms on miry bottom. 



I have so long delayed publishing the description 

 which I then sketched, and which certainly leaves much 



