113 



hos den nys nævnte Art. Paa alle de af os undersøgte Arter 

 af Phascolosoma, Onchnesoma og Tylosoma fandtes der i 

 Centrum af Hudlegemerne, eller op imod deres Udførsels- 

 kanal en Slags Hule, hvori paa hærdede Præparater altid 

 saaes en coaguleret Masse, der neppe kunde være andet end 

 stivnet Slim (Fig. 21 f). Den Særegenhed, der findes hos Ph. 

 Stromhi, nemlig at der i Cuticula omkring Aabningen af 

 en Del af Hudlegemerne forekommer et Pigment, — gjen- 

 fandt vi hos Ph. Lovénii ved alle Hudlegemerne. Pig- 

 mentet er her gulgrønt, ligger mod Cuticulas Overflade, 

 som tæt sammenpakkede, kantede Legemer (Fig. 21 g, g), 

 hvorimod det længere borte fra Aabningen er mere spredt 

 og har et straalet, næsten krystallinsk udseende (Fig. 

 21 h, h). Hos Onchnesoma Steenstrupii forekommer et 

 lignende Pigment, men ikke saa grovkornet, og heller 

 ikke omkring Hudlegemernes Aabning; — her danner det 

 smaa paa Cuticula fremragende Klumper (Tab. 15, Fig. 

 34 a, a, a), der over hele Snabelen indtage en meget 

 regelmæssig, ringförmig Anordning, Nedover Kroppen 

 taber det sig, men findes ogsaa her, dog temmelig 

 spredt. 



Hudlegemerne hos Sipunculiderne ere forsynede med 

 Nerver, saaledes at der til hvertLegeme gaar en Nervestreng 

 ind igjennem Basaldelen, og synes at tabe sig hos nogle Ar- 

 ter i Kapselen. Nogen Sikkerhed med Hensyn hertil har det 

 ikke været os muligt at komme til, selv med de stærkeste 

 Forstørrelser. Baade Leydig, Semper, Ehlers og Keferstein 

 have paavist disse Nerver; og Leydig opstillede den Me- 

 ning, at Hudlegemerne vare Nerveende-Apparater, hvortil 

 Ehlers og Keferstein sluttede sig, — idet de forlod deres 

 tidligere havte Anskuelse, nemlig den, at Hudlegemerne 

 vare Secretionsorganer. Graber derimod benægter ganske 

 Tilstedeværelsen af Nerver. At han ingen saadanne har 

 fundet paa de Phascolosoma-Arter, han har undersøgt, er 

 klart nok; men deraf at drage den Slutning, at ingen 

 Nerver findes, forekommer os at være temmelig voveligt, 

 al den Stund de af meget dygtige Forskere ere paaviste. 

 Vi kunne godt forstaa, at Graber ikke har fundet de her 

 omtalte Nerver hos Phascolosomaerne ; thi de ere her saa 

 ulige langt vanskeligere at demonstrere, end hos Sipunc- 

 lerne, især paa hærdede Præparater, og dog tør det hænde, 

 at Graber virkelig har seet Nervestrengen, der gaar ind i 

 Hudlegemet, men antaget den for at være en Prolonga- 

 tion af en Ringmuskelstreng. Vi skulle kun her bemærke, 

 at Nervestrengen efter Døden er i sit Udseende noget 

 forskjellig fra hvad den er i levende Live, — den antager 

 nemlig en kornet Structur; og Graber har jo kun havt 

 døde og i Spiritus opbevarede Exemplarer til sine Un- 

 dersøgelser. Hos Onchnesoma Steenstrupii sees Hud- 

 legemernes Nerver forholdsvis let i den tyndhudede Snabel 

 hos det levende, eller bedre hos det døende Dyr. 



cuticular body lie freely (fig. 21 d). In the Ph. squamatum 

 and Onchnesoma Steenstrupii, these cells are neither so 

 large nor so cylindrical as in the species last named. In 

 all the species which we have examined of the Phascolo- 

 soma, Onchnesoma and Tylosoma, there was found in 

 the centre of the cuticular bodies, or up towards their 

 eductive canal, a sort of cavity, wherein in hardened pre- 

 parations there could always be discerned a coagulated 

 mass, which could scarcely be anything else but stiffened 

 mucus (fig. 21 f). The peculiarity observed in the Ph. 

 Strombi, namely that a pigment appears round about 

 the aperture of a part of the cuticular body, was also 

 recognised by us in Ph. Lovénii in all the cuticular bodies, 

 The pigment is here yellowish green, and lies against the 

 surface of the cuticle in the form of closely packed an- 

 gular bodies (üg, 21 g, g), while further from the aperture 

 it is more diffused, and has a radiating nearly crystal- 

 line appearance, (üg. 21 h, h). In the Onchnesoma Steen- 

 strupii, there appears a similar pigment; but it is not 

 so coarsely granulated, nor found around the aperture 

 of the cuticular bodies. In this species it forms small 

 prominent lumps on the cuticle (Tab. 15, fig. 34 a, a, a) 

 which occupy on the whole proboscis a very regular an- 

 nular arrangement. On the lower part of the body it 

 nearly disappears, but is still here and there visible, 

 though much diffused. 



The cuticular bodies in the Sipunculidæ possess nerves; 

 so that to each body there goes a nervous cord in through 

 the basal part, and appears in some species to lose itself 

 in the capsule. It has not been possible for us to arrive 

 at any certainty in this respect, even with the most powerful 

 magnifiers. Leydig, Semper, Ehlers and Keferstein have 

 pointed out these nerves; and Leydig emitted the opinion 

 that the cuticular bodies were the terminal apparatus of 

 nerves; in which opinion Ehlers and Keferstein concurred, 

 abandoning their former views, that the cuticular bodies 

 were organs of secretion. On the other hand Graber 

 denies entirely the existence of nerves. That he has not 

 found any in the species of Phascolosoma which he has 

 examined, is clear enough; but thence to draw the in- 

 ference that there are none, appears to us to be rather 

 rash, seeing that very able naturalists have pointed them 

 out. We can well understand that Graber has not found 

 the nerves here noticed in the Phascolosoma; as they are 

 so incomparably more difficult to indicate than in the 

 Sipunculus, especially in hardened preparations; and yet 

 it is possible that Graber really has seen the nervous 

 cord entering the cuticular body, but presumed it to be 

 a prolongation of an annular muscle-fibre. We shall only 

 here remark that the nervous cord is after death rather 

 different in appearance from what it is during life; as it 

 assumes a granulated structure; and Grab er has had only 

 dead specimens and specimens preserved in spirit to ex- 

 amine. In the Onchnesoma Steenstrupii, the nerves of 

 the cuticular body are comparatively easy to see in the 

 thin-skinned proboscis of the living animal, or still better 

 in the dying animal. 



