126 THEEL, NORTHERN AND ARCTIC INVERTEBRATES. I. SIPUNCULIDS. 
Plate XIlI. 
Onchnesoma squamatum (KOREN and DANIELSSEN). 'P. Trondhjem Fjord. 
Figs. 183—184. 
The body cut open in order to exhibit the internal organisation. 
d. diverticle. — fm. fixing wmuscles, — i. intestinal spiral. — oe. oesophagus. — ne. nerve- 
cord. —r. rectum broken off. — rm. retractor muscle torn off anteriorly and highly contracted, 
so that, together with a part of oesophagus, it becomes situated posteriorly in the body-cavity. 
Fig. 183. 
— s. segmental organ. 
» 184. The anal portion of the proboscis cut open. 
anus with fixing anal muscles. — ne. nerve-cord. — r. 
The same animal. 12. 
a. rectum. 
Fig. 185. Onchnesoma Steenstrupii KorREN and DANIELSSEN. 15, 
The body cut open to show the internal organisation. 
Fig. 185. 
fm. fixing muscles. — i. intestinal canal somewhat deranged. — ne. nerve-cord. — oe. oesophagus. 
— Yr. rectum. — rm. retractor muscle. 
Front views of the tentacular-ecrown. 
es. ciliated sense-pads. — m. mouth. — D. dorsal side. — V. ventral side. 
Fig. 186. Phascolosoma vulgare (BLAIND.). 39. Bohuslän. 
Fig. 187. Phascolosoma eremita (M. Sars). 9. Mosselbay. 
3 
Fig. 188. Phascolosoma elongatum KEFERSTEIN. 39. Gullmar Fjord. 
Fig. 189. Phascolosoma Trybomi n. (2). 15. Half of the erown. The Sound. 
Fig. 190. Phascolosoma procerum MösBius. 59. Gullmar Fjord. 
