123 



Actinierne, idet der paa begge Sider af hvert Septum er 

 Longitudinelle Muskler, saa at ethvert af dem synes at 

 være forsaavidt selvstændigt, som de ikke for at danne et 

 Par tiltrænge at vende deres homologe Sider, det vil sige 

 de longitudinelle Muskler, mod hverandre, da dette ifolge 

 Anordningen nødvendigvis maa saa være. 



Med Hensyn til Længdemusklernes Stilling paa Septa 

 forekommer det mig. at Forholdet ligner overmaade meget 

 det, jei: har angivet baade hos de Edwardsier, jeg har 

 undersøgt, og hos de to nye Slægter Fenja og Ægir, som 

 senere skulle omtales. Hos ingen af disse ere Septa stil- 

 lede parvis, og jeg er derfor mest tilboielig til at anse 

 Septaerne hos Mardoll for ikke at være parrede, men at 

 der er 18 fuldstændige og 18 ufuldstændige Septa, hvoraf 

 to af de forste og to af de sidste kunne ansees som Ret- 

 ningssepta. Tab. XXI, Fig. 17 a. b. Mardoll hai' for- 

 resten saameget tilfælles med Zoantheerne, at den vistnok 

 bør rækkes ind i denne Gruppe. 



Svælgroret er meget kort, næsten cylindrisk; paa dets 

 udvendige, næsten glatte Side. hvor Macrosepterne ere 

 fæstede, er der et cilierende Epithel, dannet af temmelig 

 korte Cylinderceller med deres Kjerne og Kjernelegeme. 

 Tab. XXI, Fig. 16 /; indenfor dette sees transverselle 

 Muskelfibre, Tab. XXII. Fig. 6 b. der ligge tæt til det 

 ikke meget brede Bindevævslag, Tab. XXII. Fig. 6 c. Paa 

 den indre Flade af dette Bindevæv er der et Lag temmelig 

 stærke Længdemuskler, Tab. XXII. Fig. 6 d, som beklædes 

 af et Endothel, bestaaende af meget lange, cilierende Cylin- 

 derceller, Tab. XXII, Fig. 6 e, hvorimellem sees hist og 

 her encellede, kolbeformede Slimkjertler, Tal). XXII. Fig. 

 ti _/, samt en stor Mængde Nematocyster. Tab. XXII, Fig. 

 6 g. Paa Svælgrørets indre Flade er der en Svælggrube 

 (Siphonoglyph), som er temmelig dyb med tykke, afrundede 

 Rande, indtagende hele Rorets Længde, og hvori ikke sees 

 Nematocyster, Tab. XXII. Fig. 7 b; den øvrige Del af 

 Fladen er foldet og slimet. Tab. XXII. Fig. 7 d. 



Tentaklerne ere udvendigt beklædte med et Ectoderm, 

 bestaaende af meget hoie Cylinderceller. Tab. XXII. Fig. 

 2 a. hvorimellem sees en utallig Mrengde Nematocyster. 

 Tab. XXII. Fig. 2 b. Indenfor Ectodermet er et Lag med 

 stærke Længdemuskler. Tab. XXII, Fig. 2 c. der stode 

 umiddelbart til et Bindevævslag, forsynet med Bindevævs- 

 legemer og Ernæringskanaler, Tab. XXII. Fig. 2 d. Paa 

 Bindevrevets indre Væg sees temmelig stærke, cirkulære 

 Muskler. Tab. XXII, Fig. 2 e. der beklædes af et Endo- 

 thel, dannet af meget hoie. cilierende Cylinderceller. Tab. 

 XXII, Fig. 2 ./. 



Jeg omtalte tidligere, at Polyperne ikke stode i direkte 

 Forbindelse med hinanden men ved Kanaler, der vare næsten 

 retliniede, hvor der kun var to sammenhængende Polyper, 

 saa at Ernæringsvædsken hos den ene Polyp med Lethed 



ln tlie second place, the muscular arrangement is dif- 

 ferent from that which is usually found in Actinidæ, as 

 fchere are longitudinal muscles on both sides of each septum, 

 so that each of them appears to be so far independent, 

 that thev do not require, in order to form a pair, to turn 

 their homologous sides, that is to say tbe longitudinal mus- 

 cles, towards each other. as this according to their arrange- 

 ment must of necessity be so. 



With regard to the situation of tbe longitudinal mus- 

 cles on the septa. it appears, to me. that the relations 

 resemble in a great degree those I have stated in respect 

 of the Echvardsiæ I have investigatcd, and of the two new 

 genera Fenja and Ægir, to be subsequently dealt with in 

 this memoir. In none of these are the septa placed in 

 pairs, and I am, therefore, most disposed to consider, that 

 the septa of Mardoll are not paired. hut that there are 

 18 perfect and 18 imperfect septa, of which two of the 

 first-named and two of the last-named may be considered 

 to be directive septa (Pl. XXI, fig. 17 a. b). Mardoll has, 

 otherwise. so much in common with Zoanthidæ that it 

 ought assuredly to be placed in that group. 



The gullet-tube is very short, almost cylindrical ; upon 

 its external, almost smooth side, where the macrosepta are 

 attached, there is a ciliating epithelium formed of rather 

 short cylinder-cells with their nucleus and nucleus-corpuscle 

 (Pl. XXI, fig. lb' /'); to the inside of that transversal 

 muscle-fibres are observed (Pl. XXII. fig. ti b\. ly ing close 

 to the not very broad laver of connective-tissue (Pl. XXII. 

 fig. 6 c). Upon the inner surface of that connective-tissue 

 there is a laver of rather strong longitudinal muscles (Pl. 

 XXII, fig. 6 d), which are clad with an endothelium con- 

 sisting of very long ciliating cylinder-cells (Pl. XXII, fig. 

 6 e), between which are seen, here and there, unicellular, 

 claviform, mucous glands (Pl. XXII, fig. 6 f), also a great 

 multitude of nematocysts (Pl. XXII, fig. 6 17). Upon the 

 inner surface of the gullet-tube there is a gullet-groove 

 (syphonoglyph) which is rather deep, with thiek rounded 

 margins, and occupies the entire length of tbe gullet-tube; 

 in it no nematocysts are observed (Pl. XXII, fig. 7 b); 

 the remåining part of the surface is folded and viscous 

 (Pl. XXII. fig. 7 d). 



The tentacles are clad externally with an ectoderm 

 consisting of very high cylinder-cells (Pl. XXII, fig. 2 a), 

 between which there are seen an innumerable multitude 

 of nematocysts (Pl. XXII, fig. 2 b). Inside the ectoderm 

 there is a layer of strong longitudinal muscles (Pl. XXII. 

 fig. 2 c). which immediately unites to a connective-tissue laver 

 furnished with connective-tissue corpuscles and nutritory 

 ducts (Pl. XXII, fig. 2 d). Upon the inner wall of the 

 connective-tissue rather strong circular muscles are observed 

 (Pl. XXII. fig. 2 e), which are clad with an endothelium 

 formed of very high. ciliating cylinder-cells (Pl. XXII. 



fig. 2 /)■ 



I mentioned, previously, that the polyps did not stand 

 in direct connection with each other, but by ducts that 

 were almost rectilineal. where there were only two united 

 polyps. so that the nutritory fluid of the one polyp could 



16* 



