94 



Farven. Skeden er graagrøn, dels lysere, dels 

 mørkere eiter Lerets Beskaffenhet!, hvormed den er infil- 

 treret. Kolumnen er bleg rosenrød, naar den er udstrakt, 

 men sarnm ent rukken er den mørkere rosenrød ; i den bagerste 

 Ende spiller den lidt i det Violette. Længdefurerne ere 

 lidt mørkere rod end Mellempartierne. Mundskiven har 

 Kroppens Farve. Tentaklerne ere næsten movkerode, spil- 

 lende noget i det Karmosinrode, Tab. V. Fig. 1. 



Ved Tversnit viser Skeden sig at være dannet af en 

 Slimmembran, hvori Ler og andre fremmede Legemer ere 

 indleirede. Denne Slimmembran er meget tynd. seig 

 og fastklæbet til Kropshuden uden egentlig at være 

 organisk bunden til denne, saaledes som Tilfældet er hos 

 Slægten Phellia. Det synes mere som om Sugevorterne 

 holde den fast; thi netop hvor disse findes. sees altid 

 Rester af Membranen, naar den forresten er bortskyllet. 

 Tab. V. Fig. 1. 



Kropshndens ydre Flade har et temmelig bredt Ecto- 

 derm. der bestaar af lange Cylinderceller. Tab. XV. Fig. 7 a. 

 som paa den nøgne, øverste Del have temmelig lange Cilier, 

 ligesøm der her er en stor Mængde Nematocyster og en- 

 cellede Slimkjertler. Paa den Del af Kroppen, som er 

 bedækket af den inkrusterede Slimmembran, ere Nemato- 

 cysterne yderst sjeldne, imedens Slimkjertlerne ere her ligesaa 

 hyppige som paa den nøgne Del. Indenfor' Ectodermet ei- 

 et bredt, fibrillært Bindevævslag med mange Bindevævs- 

 legemer og fine Ernæringskanaler, Tal). IX V. Fig. 7 h ; 

 henimod den indre Flade af dette Bindevæv iagttages 

 et forholdsvis bredt Belte, bestaaende a f cirkulære Muskleri 

 Tab. XV, Fig. 7 c. Hvorvidt Muskeltibrillerne samle sia i 

 Bundter eller ere leirede lige ved Siden af hverandre, er 

 vanskeligt at afgjøre; paa Længdesnittet synes det første 

 at være Tilfældet, Tal). XV. Fig. 8 a. Endothelet. som 

 beklæder Gastralhulhedens Flade, bestaar af lange Cylinder- 

 celler. der bære lange Cilier. 



Der er 6 Par fuldstændige Septa, som tåge deres 

 Begyndelse i den bagerste Ende. omkring Sluttemuskelen 

 for Caudalaabningen, Tab. XV. Fig. 9 a. hvorjde ere meget 

 smale, men blive alt bredere og bredere, jo længer de 

 komme øp, saa at de omtrent paa Midten af Gastralhul- 

 hedens Flade ere 3""" brede, Tab. XV, Fig. 9 b, men af- 

 tage nu noget i Bredden, idet de fæste sig paa Svælgrøret, 

 Tab. XV. Fig. 9 c, d. og blive atter meget smale ved 

 Insertionen paa Mundskiven. Fig. 9 e. Af disse Septa ei- 

 der 2 Par. der udpræge sig som Retningssepta og ere 

 fæstede til Svælgrorets Bug- og Rygside. Tab. XV. Fig. 10 «; 

 de øvrige 4 Par ere fæstede 2 paa hver Side af Svælg- 

 røret. Tab. XV. Fig. 10 //. Samtlige Septa ere som sæd- 

 vanlig! førsvnede med Længde- oa: Tvermuskler. 



Paa Retningssepta ere Længdeniusklerne placerede 

 paa den ydre Flade og vende fra hverandre i det inter- 



Tlie rolour. The sheath is greyish-green. lighter or 

 darker in colour according to the nature of the clay with 

 whih it is infiltrated. The column is pale rosy-red when 

 it is extended, but dark rosy-red when contraeted; in the 

 posterior extremity it has a slightly violet play of colour. 

 The longitudinal furrows are a little darker in colour than 

 the intermediate parts. The oral disc has the same colour 

 as the body. The tentacles are almost dark red with a 

 slight erimson-red play of colour (Pl. V, fig. 1). 



In transversal sections the sheath appears to be 

 formed of a mucous membrane, in which clay and other 

 foreign bodies are entrenched. This mucous membrane is 

 very thin and viscid, and is firmly glued to the integument 

 of the body without, however, being really organically at- 

 tached to it, like what is the ca.se in the genus Phellia. 

 It looks more as if the suckers held it fast, as, just at 

 the points where they are met with. remains of the 

 membrane are always observed when in all other parts it 

 is washed off | Pl. V. fig. 1). 



The external surface of the integument of the body 

 has a rather broad ectoderm, consisting of long cylinder- 

 cells (Pl. XV. fig. 7 a), which. upon the bare. uppermost 

 part have pretty long eiliæ, whilst, here. also. there is a 

 great abundance of nematocysts and unicellular mucous 

 glands. On the part of the body covered by the encrusted 

 mucous membrane. the nematocysts are extremely rare. 

 whiKt the mucous glands are. here, as frequent as upon 

 the bare part. Inside of the ectoderm there is a broad, 

 fibrillous. connective-tissue laver with numerous connective- 

 tissue corpuscles and fine nutritory ducts (Pl. XV. fig. 7 &); 

 and towards the inner surface of this connective-tissue 

 there is observed, a relatively broad belt, consisting of 

 circular-muscular fibres (Pl. XV. fig. 7 c). It is difficult 

 to determine whether the musele fibrils collect themselves 

 into bundles or are seated alongside each other. In longi- 

 tudinal sections the first-named arrangement seems to be 

 the .ase (Pl. XV. fig. 8 a). The endothelium that clothes 

 the surface of the gastral cavity, consists of long cylinder- 

 cells earrying long eiliæ. 



There are li pairs of perfect septa, which have their 

 origin in the posterior extremity. round the sphincter of 

 the caudal aperture (Pl. XV. fig. 9 a); they are. here. 

 very narrow, but become broader and broader the farther 

 they extend upwards, so that. at about the middle of the 

 surface of the gastral cavity they are 3'""' in breadth (Pl. 

 XV. fig. 9 6), but flien diminish somewhat in breadth 

 as they secure themselves upon the gullet-tube (Pl. XV. 

 fig. 9 r. (/, becoming, again, very narrow at the insertion 

 on the oral disc (Pl. XV. fig. 9 e). Of these septa there 

 are 2 pairs that distinguish themselves as directive septa. 

 and which are secured to the ventral aud dorsal side of 

 the gullet-tube (Pl. XV. fig. 1<> a); the other 4 pairs of 

 septa are secured, 2 upon each side of the gullet-tube 

 (Pl. XV. fig. 10 b). All the septa are furnished. as usual, 

 with longitudinal aud transversal muscles. 



On the directive septa. the longitudinal muscles are 

 seated on the outer surface. and face from each other in 



