118 
Figs. 128 
Fig. 128. 
» 129. 
30 
5 Hl 
Nl D25 
>» MBB 
5 NSX 
> ND 
» 136. 
Fig. 137 
» HIS 
> NM 
THÉEL, NORTHERN AND ARCTIC INVERTEBRATES. I. SIPUNCULIDS. 
Plate IX. 
136. Physcosoma Lovenii (KOREN and DANIELSSEN). The same as before. 
Section” through a gland from the posterior extremity of the trunk. 139. 
c. cutiele. — cs. concentric structure of the cuticle. — e. epithelium. — 1 m. longitudinal 
muscles, not arranged in bundles. — p. layer of pigment surrounding the pore. — tm. trans- 
verse muscles in irregular close-lying bundles. — ec. gigantic excretory cells. 
Sample of skin from the proboscis with the 25th, 26th and 27th rows of hooks. Seen 
from above. 130. ; 
gl. glandular bodies between the rows of hooks. — Im. interspaces between the transverse mus- 
cular bundles and the continuous layer of longitudinal muscles. — tm. transverse muscular bundles. 
Four hooks of the 6th row in natural position. Side view. 350. 
Two isolated hooks of the 25th row. Side and upper views. 350. 
An isolated hook of the 26th row. Side view. 350. 
Side view of two hooks of the 27th row. 350. 
Longitudinal section through a part of the wall of the proboscis to sbow the collar and 
the arrangements of the hooks. The first 12 rings of hooks. 5. 
a. smooth place behind the tentacles. — b. annular collar-fold. — c. space behind the collar-fold, 
forming with the tissues behind a deep and narrow annular furrow, where new rings of hooks 
successively arise in new-formed narrow and rather deep furrows. — d. the foremost hook- 
bearing and hook-producing furrows. — e. small glands. — f. hooks broken off. — 1m. con- 
tinuous layer of longitudinal museles. — tm. transverse bundles of muscles forming together 
with the epithelium and the cutiele circular folds, higher and narrower anteriorly, decreasing 
in height posteriorly but becoming gradually broader. 
Magnified view of the anterior part of the former figure. Lettering as before. 130, 
Magnified view of the posterior part of Fig. 134. Lettering as before. 130, 
Figs. 137—145. Sipunculus priapuloides KoREN and DANIELSSEN. Bergen. 
The animal drawn in natural size. 
a. anus. — s. opening of the segmental organ. — g. glans. 
The proboscis opened along the dorsal surface to show the nerve-cord, its ramifications 
ete. + 
dr. dorsal retractors. — in. interspaces between the longitudinal muscle-bundles, covered by the 
peritoneal membrane in order to form longitudinal canals provided with a series of transverse 
openings into the body-cavity. — Im. longitudinal muscle bundles. — ne. nerve-cord with its 
ramifications. — nr. nerye-ring. — oe. oesophagus. — so. sensory pit. — vr. ventral retractors. 
Longitudinal section through the tentacular portion of the animal, to show the brain 
and sensory pit. 29. 
b. brain. — be. body-cavity. — so. sensory pit. — t. tentacles. 
Figs. 140—145. Different views of papille of the proboscis. Fig. 140. Upper view of a papilla 
drawn with the light thrown upon the object. 56. — Fig. 141. Another papilla of the 
same kind. 25. — Figs. 142—143. Upper and side views of papille, drawn with the 
light transmitted through them. >. — Figs. 144—145. Side views of papille, of which 
Fig. 145 represents one of these lying furthest to the front. Drawn with the light 
thrown upon the object. 36, 
