30 THÉEL, PRIAPULIDS AND SIPUNCULIDS OF THE SWEDISH ANTARCTIC EXPEDITION 1901 — 1903. 



The total length of the specimens from »Maj viken» in Cumberland Bay was 

 stated to be 16 or 17 mm. Låter on I have met with two other specimens from 

 »Grytviken» in the same fjord which are about twice as long and have the body- 

 cavity filled with eggs. 



The anal aperture is situated at the middle of the body, and the pores of the 

 segmental organs have their places on a level with that opening. The dorsal retractors 

 are attached slightly behind the middle of the body and the ventral ones further 

 backwards (fig, 70). 



The intestinal tube with its 14 double turns is free posteriorly and is furnished 

 with a spindle-shaped muscle. A fixing muscle is attached to the posterior part of 

 the oesophagus. 



I have not been able to discover any contractile vessel along the oesophagus, 

 though such a tube may very likely exist. The reproductive organs are well developed. 



This species must be related to Phascolosoma cylindratum of Keferstein, but 

 differs from it by the form and arrangement of the hook, by the presence of pa- 

 pillse etc. 



Phascolosoma nordenskjöldi n. 



Pl. III, tigs. 35—41. 



Habilat. —Falkland Islands: Port William, 12 m., sand and gravel, 3 /9 1902. 

 Three small specimens. — South Georgia: »Sydfjorden», 195 m., clay with stones, 

 29 /b 1902. Several small specimens, the largest measuring about 9 mm. in lenght. — 

 »Moränfjorden», 64—74 m., grayish clay with stones, 1S 5 1902. Some minute specimens. 



Total length oj the largest specimen about 9 mm. Body elongate, subcylindrical, 

 having the posterior extremity more or less rounded. Two small tentacle-lobes. Skin 

 annulate, shining, with small papillce scattered över the body, but slightly more crowded 

 posteriorly. Behind the tentacles a girdle of hooks and papillce. Two free segmental 

 organs. Muscular layers of the body-ivall continuous, not separated into bands. Two 

 ventral and two dorsal retractors. Intestinal spiral composed of about 14 turns and not 

 attached posteriorly. 



The most characteristic feature of this species is the presence of only two ten- 

 tacle-lobes (fig. 37) of quite the same shape as those in Phascolosoma (Petalostoma) 

 minutum Keferstein. Also in other respects there exists a certain resemblance. 

 Supposing that the descriptions of Keferstein and Selenka had been correct, then 

 I should not have hesitated to ref er this form to Ph. minutum, but since Paul 1 has 

 shown that the species of Keferstein is provided with only two retractors, the 

 antarctic samples may represent a new species. 



The body-wall is folded in a series of rings by means of numerous close-lying 

 transverse ridges, which at the posterior extremity of the body are broken up and 

 wrinkled, thus giving rise to an irregular net-work (figs. 40 and 41). The small 



1 Uber Petalostoma minutum. Zool. Jahrbuchcr. Pd. 29. Jcna 190'J. 



