\ 



139 



ten; r 1 Rectum; sm Spindelmuskel; le contractilt Kar: 



o slangeformigt Organ 

 s, 8 Segmentalorganer. 



n Nervestreng; t, t Tarmspiral; 



PHASCOLOSOMA (S1PUNCULUS) VUL- 

 GARE, Blainville. 



Diet. des Se. nat. 49, 1827, Pag. 312, 313. Atlas, Vers, P). 33, 

 Fig. 3, 3. 



Phaseolosoma vulgare, Diesing, 

 Syst. helminth. II, 1851, Pag. 65. 



Phaseolosoma vulgare, Keferstein. 

 Zeitschrift f. wiss. Zoologie, XII, Pag. 39, Taf. 3, Fig. 3. 



Phaseolosoma elongatum, Keferstein. 

 Zeitschrift, f. wiss. Zoologie XII, Pag. 39, Taf. 3, Fig. 5, 14, 

 Taf. 4, Fig. 2—6. 



Sipunculus elongatus, Quatref. 1. c. II, Pag. 619, 1865. 



Kroppen omtr. 60 Mm. lang, valsefor mig, noget co- 

 nisk tilspidset i dens bagerste Ende, og besat med tem- 

 melig smaa Papiller, der paa den forreste Del og ved 

 Grunden af Snabelen samt paa den bagerste Ende staa 

 meget tættere sammen, ere noget større, og danne et mør- 

 kere farvet Belte. Snabelen indtager omtrent Kroppens 

 halve Længde, er forsynet med lignende Papiller, og paa 

 dens forreste, noget opsvulmede Del sees 8—10 Hinge 

 med hornagtige Hager, der ere lidt krumbøiede. Paa 

 Snabelen en Krands traadformige Tentakler, omtr. 16 i 

 Antal. Huden temmelig fast; paa dens indvendige Flade, 

 der er gulhvid, stærkt iriserende, sees de almindelige to 

 Muskellag, der ere temmelig tynde. 4 Retractorer, hvoraf 

 Bugretractorerne ere de længste og udspringe paa Grænd- 

 sen af den forreste og midterste Trediedel af Kroppen 

 med en noget bredere Basis, hvorom et tyndt hvidagtigt 

 Organ slynger sig. Rygretractorerne ere meget kortere 

 og udspringe fra Kropshulhedens forreste Del. Fortil i Sna- 

 belen forene de sig og omgive Spiserøret. Dette er no- 

 get kort, og ledsaget af det contractile, slangeformige 

 Kar, der er temmelig tykt og af en hvid Farve. Tarmen 

 er meget lang, danner omkring 50 Slyngninger, og naar 

 lige til Bunden af Kropshulheden. Den første Slynge, 

 ligesom Spiserøret, er befæstet ved flere tendinøse Mu- 

 skeltraade. Endetarmen kort, og dens yderste Ende fast- 

 heftet til Kropsvæggen ved mange tendinøse Traade. 

 Strax foran Endetarmen udspringer en Spindelmuskel, der 

 følger denne, gaar et Stykke bagover indeni Tarmspiralen 

 og fæster sig paa Kropsvæggen. Segm entalorganerne 

 frie, meget lange og stærkt contraherede. Generations- 

 organet tilheftet Tarmen, hvis Slyngninger det ganske om- 

 slutter i en stor Udstrækning, indeholdende en Masse Æg, 

 hvoraf mange løse ogsaa fandtes i Kropshulheden. Ner- 

 vestrengen løber imellem begge Bugretractorernes Grund- 

 del, og afgiver de sædvanlige Grene til Hud, Spiserør og 

 Tarm. 



fusiform muscle; k contractile vessel, o serpentine organ ; 

 n nervous cord; t, t spiral of intestine; s, $ segmental, 

 organs. 



PHASCOLOSOMA (SIPUNCÜLUS) FUL- 

 GARE, Blainville. 



Diet. des. se. nat. 49, 1827, p. 312, 313. Atlas, Yers, PL S3, 

 fig. 3, 3. 



Phaseolosoma vulgare, Diesing. 

 Syst. helminth 11, 1851, p. 65. 



Phaseolosoma vulgare, Keferstein. 

 Zeitschrift f. wiss. Zoologie, XII, pag. 39, Taf. 3, fig. 3. 



Phaseolosoma elongatum, Keferstein. 

 Zeitschr. f. wiss. Zoologie XII, p. 39, Taf. 3, fig. 5, 14, Tat 

 4, fig. 2-6. 



Sipunculus elongatus, Quatref. 1. c« II, p. 619, 1865. 



The body about 60 Mm. long, cylindrical, somewhat 

 conically tapered at its posterior extremity, and covered 

 with rather small papillæ, which, on the foremost part 

 and on the basis of the proboscis, as also on the hin- 

 dermost part, stand much more closely together, are 

 somewhat larger, and form a darker colored belt. The 

 proboscis occupies about half the length of the body, 

 is covered with similar papillæ, and on its . anterior, 

 somewhat enlarged part, has 8—10 rings with horny 

 hooks which are a little bent. On the extremity of the 

 proboscis, a circlet of filiform tentacles, about 16 in 

 number. The skin rather firm; on its interior surface, 

 which is yellowish white, and strongly iridescent, there ap- 

 pear the usual two layers of muscles which are rather thin. 

 4 retractors, of which the ventral retractors are the long- 

 est and issue from the limits of the anterior and middle 

 thirds of the body, with a somewhat broader basis, round 

 which a thin whitish organ entwines itself. The dorsal 

 retractors are much shorter, and issue from the foremost 

 part of the perivisceral cavity. They unite themselves in 

 front in the proboscis, and go round the oesophagus. 

 The latter is somewhat short and accompanied by the 

 contractile serpentine vessel, which is rather thick and 

 of a white color. The intestine is very long, forms about 

 50 circumvolutions, and extends quite to the bottom of 

 the perivisceral cavity. The first circumvolution and the 

 gullet are attached by several tendinous muscular filaments. 

 The rectum is short, and its exterior end fixed to the 

 wall of the body by many tendinous filaments. Immedi- 

 ately in front of the rectum, there issues a fusiform 

 muscle, which accompanies it, goes some distance back- 

 ward inside of the intestinal spiral and attaches itself to 

 the wall of the body. The segmental organs free, very 

 long and strongly contracted. The organ of generation 

 is attached to the intestine, the circumvolutions of which 

 it encloses entirely to a great extent, and contains a 

 multitude of ova, of which many were also found loose 

 in the perivisceral cavity. The nervous cord runs be- 

 tween the bases of both the ventral retractors, and fur- 

 nishes the usual branches to the skin, the oesophagus 

 and the intestine. 



