132 



stærke, krumme Hager og bærer en Ilad med 20—24 cy- 

 lindriske Tentakler. Huden mat, svagt iriserende, fast 

 og lialvgjennemskinnende. Paa dens indre Flade de to 

 sædvanlige Muskellag. To Retractorer, der ere temmelig 

 tykke, udspringe med en bred Basis omtr. fra Midten af 

 Bugfladen og gaa adskilte hen til Snabelens forreste Del, 

 hvor de omgive Spiserøret (Fig 26 r). Ved Retractorer- 

 nes Grunddel sees et tyndt, slangeformigt Organ (Fig. 

 26 o). Spiserøret, der er temmelig kort og ledsaget af 

 det contractile Kar, gaar over i en lang Tarm, der dan- 

 ner omkring 36 Slyngninger, hvoraf den bagerste naar 

 lige til Kropshulhedens Bund (Fig 26 sp). Tarmspiralen 

 er paa et Par Steder fæstet til Kropsvæggen, men dens 

 bagerste Ende er fri. Rectum kort (Fig. 26 re). Ingen 

 Spindelmuskel. 2 Segmentalorganer (Fig. 26 s, s), der 

 hænge frit og ere orangefarvede. Nervestrengen løber 

 mellem Retractorernes Grunddel (Fig. 26 n). 



Farven lysegul, men paa Kroppens bagerste Ende og 

 ved Grunden af Snabelen er der et noget mørkere farvet 

 Belte. Snabelens Midtparti er næsten hvidt, stærkt perle- 

 mor-glindsende. 



Fundet i Bergensfj orden i de Gange, som dannes 

 paa Lima excavata af Cliona abyssorum, Sars, 200—300 

 Favnes Dyb, stenet Bund. Sjelden. Denne Art kommer 

 nærmest Forbes's Syrinx (Phascol.) Harveii ; men adskiller 

 sig dog fra denne derved, at Kroppen er ganske glat, 

 uden Papiller, med en utallig Mængde Hudlegemer, at 

 Kroppens bagerste Ende er afstumpet, at Huden er fast, 

 at Hagerne ere tykkere og mere krumbøiede, at der kun 

 er en Tentakelrad, at den kun har 2 Retractorer, og ende- 

 lig at Tarmen har mere end 30 Vindinger. 



ARTSCHARACTEREN. 

 Kroppen valseformig, langstrakt, glat, omtrent 10 

 Gange saa lang som tyk, besat med en utallig Mængde 

 smaa Hudlegemer, uden Papiller. Snabelen omtrent V 4 

 af Kroppens Længde, ved Grunden besat med fine Pa- 

 piller, og paa dens forreste Ende et bredt Belte af 10 — 

 12 Ringe med Hager. Tentaklerne 20-24. To Retrac- 

 torer. Farven lysegul med et mørkere Belte paa Sna- 

 belens Grunddel og paa Kroppens bagerste Ende. 



FORKLARING OVER FIGURERNE. 



Tal). 14, Fig. 25. Phascolosoma abyssorum, lidt forstørret. 



Fig. 26. n Nervestreng; o slangeformigt Organ; r Bugretractorerne; 

 re Rectum; s, s Segmentalorgan; sp Spiserør; t Tarmspi- 

 ralen. 



Fig. 27. Tvende Hager, stærkt forstørret. 



PHASCOLOSOMA PALLIDUM, Nobis. 



(Tab. 14, Fig. 22-24). 



Kroppen er stump tapformig, 28 Mm. lang, 4 Mm. 



bred, forsynet med runde i Spidsen fladtrykte Papiller, 



der ere temmelig fremragende, men blive paa den bagerste 



with 10—12 rings with strong bent hooks, and bears a 

 row of 20—24 cylindrical tentacles. The skin dull, slightly 

 iridescent, firm and half transparent. On its interior 

 surface, the two usual layers of muscles. Two retractors, 

 which are rather thick, issue with a broad basis from 

 about the middle of the ventral surface, proceding separa- 

 tely to the anterior part of the proboscis, where they 

 surround the oesophagus (fig. 26 r). At the basal part 

 of the retractors, there is a thin serpentine organ (fig» 

 26 o). The oesophagus, which is rather short and ac- 

 companied by the contractile vessel, goes over into a 

 long intestine, forming about 36 circumvolutions, of which 

 the posterior one reaches right to the bottom of the 

 perivisceral cavity (fig. 26 sp). The intestinal spiral is 

 in a few places attached to the wall of the body; but 

 its posterior extremity is free. The rectum, short (fig. 26 re). 

 No fusiform muscle. 2 segmental organs (fig. 26 s, s), 

 hang freely and are orange-colored. The nervous cord 

 runs between the basal parts of the retractors (fig. 26 n). 



The color is light yellow; but on the posterior ex- 

 tremity of the body, and at thej basis of the proboscis, 

 there is a somewhat more darkly colored belt. The middle 

 part of the proboscis is nearly white, strongly shining 

 like mother of pearl. 



Found in the Bergensfj ord in the canals formed on 

 the Lima excavata by the Cliona abyssorum, Sars, at a 

 depth of 200—300 fathoms, stony bottom. Rare. This 

 species comes nearest to Forbes's Syrinx (Phascol.) Harveii, 

 but differs however from the latter: by the body being 

 quite smooth without papillæ, with an innumerable quan- 

 tity of cuticular bodies; by the posterior part of the 

 body being truncated; by the skin being firm; by the 

 hooks being thicker and more bent; by there being only 

 one row of tentacles; by having only 2 retractors, and 

 finally by the intestine having more than 30 windings. 

 SPECIFIC CHARACTERISTICS. 



The body cylindrical, elongated, smooth, about 10 

 times as long as it is thick, covered with an innumerable 

 quantity of small cuticular bodies, without papillæ. The 

 proboscis about V 4 of the length of the body, at the 

 base covered with fine papillæ, and on the anterior ex- 

 tremity a broad belt of 10—12 rings with hooks. The 

 tentacles 20 — 24. Two retractors. The color light yellow, 

 with a darker belt on the basal part of the proboscis, 

 and on the posterior extremity of the body. 



EXPLANATION OF THE FIGURES. 

 Tab. 14, fig. 25. Phascolosoma abyssorum, slightly magnified. 

 Fig. 26. n nervous cord; o serpentine organ; r ventral retractors ; 



re rectum; s, s segmental organs ; sp oesophagus; t spiral 



of intestine. 

 Fig. 27. Two hooks, strongly magnified. 



PHASCOLOSOMA PALLIDUM, Nobis. 



(Tab. 14, fig. 22-24). 

 The body is obtusely plug-shaped, 28 Mm. long, 

 4 Mm. broad, furnished with round papillæ flattened at 

 the point, which are rather prominent, but become on 





