35 



Eftersom nu dutte GdiKifoiaiilæg voxer, men ofte 

 forst iiaar det har iiaaet iiæsten sin fulde Udvikling, for- 

 inaar det at tranige sig ud mod Overfladen af det mægtige 

 Elvtodermlag, idet det stadig si<yver et Lag Elctodermceller 

 foran sig, — det Lag, der sammen med Ektodei-nien senere 

 danner Gonnforens Va-g (Tab. IIT, Fig. 6 e). 



Under Anlægget af ..Glockenkenr' sees ofte et Hiil- 

 runi me!lm de indvandrende Ektoderniceller ; men da jeg 

 aldrig har kunnet finde noget saadant paa de senere Sta- 

 dier af Gonoforernes Udvikling, auser jeg det ikke for 

 sandsynligt, at dette Hulrnni er af nogen blivende Betyd- 

 ning. 



Hos Myriothela minuta, og ogsaa hos andre Arter, 

 der har et liegrrendset Antal Gonoforer paa hver Blastostyl, 

 anlægges vistnok forudeii disse, endel flere Gonoforer, der 

 imidlertid hænimes i sin Udvikling. ~Slan kan saaledes paa 

 Snit se Combinationer af Celler og Cellelag, der fuldstaMi- 

 dig svarer til dem. som forekommer under Gonofordannel- 

 sen, men hvor Stottelaniellen mellem de forskjellige Lag 

 er fortykket og i hvilke Gloekenkerncellerne ikk<' paa nogen 

 ]Maade er omdannet. 



Som jeg nævnte i min foreløbige Meddelelse, tindes 

 der foruden de nedenfor nævnte Arter af Mijriothela. og- 

 saa endel Brutlstykker og nogle medtagne Exemplarer. som 

 jeg ikke tinder det rimeligt at beskrive, da en saadan Be- 

 skrivelse vikle blive meget mangelfuld og bare l)riuge vild- 

 rede i Systematiken. Jeg har dog afbildet dem saavidt 

 mulig nøiagtig efter den Tilstand, hvori jeg har seet dem, 

 og kanske vil det ved senere Undersøgelser blive muligt at 

 bringe hver af dem paa sin rette Plads. Det ser ud, som 

 om visse Dele af tiem har været udsat for Indtorring, idet 

 hele Hydranthen paa sine Steder smalner af til en tin 

 Streng. Paa en Hydranth (Tal.i. III, Fig. 3) sees som en 

 liden Knop, der udgaar fra Siden af den nær ved Munden. 

 Dette er vistnok en abnorm Dannelse (Fig. 3 a viser et Snit 

 gjennem den), og kanske skyldes den en eller anden Parasit. 



Myriothela phrygia, Falir. 



(Tab. IV, Fig. t). 



Trophosome. Polypen cylinder- eller svagt kolle- 

 formet, 4 — 40 cm. hoi. nestet ved fine Traade til Under- 

 laget. Ingen Perisarc. Paa den nederste V.i sidder en 

 hel Del Blastostyler, og hele Resten af Polypen er dækket 

 med smaa koUeformede Tentakler. Diameteren er ved 

 Basis størt, medens Polypens smaleste Del findes lige oven- 

 for Blastostylerne. Blastostylerne er forholdsvis korte, og 

 har smaa, kølleformede Tentakler i sin distale Ende. 



Gonosome. Pseudomedus(jide (lonoforer, siddende 

 paa Blastostylerne. over hele disses Overflade (Han), eller 

 eller kun 2 diametralt modsat nær Blastostylernes distale 

 Ende (Hun). 



Som jeg nævnte i min forelobige Meddelelse (29) er 

 der fra Nordh.-Exp. medbragt Brudstykkor af en kolosal 

 Miirioilvla. der heldigvis blev afl^ildet af G. 0. Sårs under 



As this gonophore rudiment grows, hut often not 

 uutil it has almost reached maturity, it succeeds in foreing 

 its way out towards the surface of the thick ectodermal 

 layer, always i)ushing before it a layer of endodermal cells, 

 the layer which, together with the ectoderm, subsequentlj^ 

 forms the wall of tlie gonophores (Tab. III, fig. 6 e). 



During the formation of the ,.glockenkern"', a lumen 

 is often visible b.etween the in-wandering eetoderni cells. 

 but as I have never I)een able to tind anything of tlie 

 kind in the later stages of tlie gonopliores development, I 

 do not think it likely that this lumen is øf any permanent 

 importance. 



In Myriothela minuta, and other species with a liniited 

 number of gonopliores on eacli blastostyle, a few more 

 gonophores are indeed formed, but they are checked in 

 their development. In sections, combinatioiis of cells and 

 cellular laycrs may be seen, resembling perfectly those 

 found during the formation of the gonophores, but with 

 the structureless lamella between the various layers thicke- 

 ned, and the glockenkern cells in no way transformed. 



As I stated in my preliminary communication, tliere 

 are, besides the above-named species of Myriotliela. a few 

 fragments and some damaged specimens, which I do not 

 consider worthy of description, as such description would 

 be very imperfect, and calculated only to Itring confusion 

 into the systematisation. I have, however drawn them as 

 accurately as possible in the condition in wliich I saw 

 them ; and it will perhaps be possible, by the aid of sub- 

 sequent investigations, to give each of them its proper 

 place. Some portions of them appear to have been sub- 

 jected to shrinking, as the entire hydranth, in some in- 

 stances. tapers otf to a fine thread. On one hydranth 

 (Pl. III, fig. 3), a little bud is seen, projecting from its 

 side, near the mouth. This must be an abnormal forma- 

 tion (lig. 3 a shows a section through it), perhaps due to 

 some parasite or other 



Myriothela phrygia. Fabr. 



(PI. IV, fig. h). 



Trophosome. Polyp cylindrioal. or slightly clavate, 

 from 4 to 4(J cm. liigh, attached by fine lilaments to the 

 sub-stratum. Xo perisarc. On the polyp's lowest fifth 

 are a number of blastostyles, the remainder being cøvered 

 with small clavate tentacles. The diameter is greatest at 

 t!ie base, while the narrowest part is immediately above 

 tiie lilastostyles ; the latter are comparatively short, and 

 have small clavate tentacles at their distal end. 



Gonosome. Pseudo-medusoid gonophores sessile upou 

 the blastostyles, either covering their entire surface (male), 

 or only 2. diametrically opposite to one another, near the 

 ! distal end of the blastostyles (female). 



As I mentioned in my preliminary account (29), 



fragments of an enormous Myriothela were brought back by 



the N. Atl. Exp., drawings liaving fortunately been made 



I of it while still entire. by G. O. Sårs during the expedi- 



0* 



