114 
Fig, 
99: 
100. 
101. 
102. 
103. 
104. 
105. 
106. 
107. 
108. 
ig. 109. 
110. 
THÉEEL, NORTHERN AND ARCTIC INVERTEBRATI. SIPUNC ES. ULIDS. 
Plate VII. 
Figs. 99—108. Phascolion tuberculosum THÉEL. Koster Fjord. 
The animal opened along the dorsal surface, though off its median line. + 
d. diverticle. — dr. dorsal retractor. — i. intestine. — m. fixing muscles, — n. nerve-cord. — 
oe. oesophagus. — r. rectum. — s. segmental organ. — Vv. vessel. — vr. ventral retractors. 
The papille of the foremost part of the trunk. 36. 
The same, though just on the transition to the proboscis. 56. 
Sample of skin from the posterior part of the trunk. 35. 
Side view of the papille from the same part of the body. 36. 
Sample of skin from the anterior part of the middle of the trunk. 56. 
Side view of the papille from the same place. 536. 
Sample of skin from the posterior part of tbe middle of the trunk. 56. 
Side view of the papille from the same part of the trunk. 56. 
The papille of the hindmost part of the trunk. 36. 
Fig. 109. Phascolion strombi (MonrT.). Bohuslän. 
An animal cut open along the dorsal surface to show the internal structure. +. 
a. anus. -— d. divertiele. -— de. coils of the intestine running downwards. =-- dr. dorsal 
retractor. — i. intestine. — n. nerve-cord. — oe. oesophagus with its vessel. — r. rectum. 
— uc. coils of the intestine running upwards. — vr. ventral retractors. 
Fig. 110. Phascolion strombi (MonTt.), Spitzbergen. Horn Sound. 
An animal opened along the dorsal surface. + 
bl. a small bladder at the end of the vessel. — m. fixing muscles. Other letters as -before. 
