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more or less rounded outline. In the hinder body-half the lateral 
lines converge more, while the anterior, part of the body may 
present a half-circular outline. The extreme posterior end is broadly 
rounded. The body has its greatest breadth anterior to the mouth 
and is in the central area of great thickness. This gradually dimi- 
nishes toward the margin where the body is leaflike thin. Owing 
to the contracted State of the body (formalin preservation used), 
the edge is always more or less folded. The consistency of the 
animals is remarkably tough. 
The tentacles show a very good development. They are large 
and evidently very contractile, and, which is of special interest, 
they are retracted into deep specially formed depressions. The 
furrow surrounding each tentacle is shown in text-figure 22. It is 
very deep. Thus it is only the tips of the tentacles that project 
above the edge of the furrow, giving the false impression on the 
reproduced photo (Plate III, Fig. 10) that the tentacles have a low, 
half-globular shape. In reality they are also in the preserved State 
rather long and stout (Plate IV, Fig. 23). There is no question but 
that these depressions are no casual formations, since they reoccur 
in all the specimens, but that they represent a special feature for 
the protection of the tentacles. When thus the tentacles are retracted 
by means of strong retractor fibres, a veritable sheath surrounding 
them is formed. The compact and thick basement membrane of 
the body becomes in the tentacles of decided thinness, which 
appears already at the outer border of the furrow-like depression 
(Plate IV, Fig. 23). 
Colour: The upper surface of the body is nicely mottled or 
sprinkled with dots of a brownish tint. Their real colour is pure 
fuscous or rather fusco-ater but, as the patches are partly hidden by 
the overlying, thick, yellow-grey epidermis, the effect becomes 
duli when the epidermis is undamaged. The pigment patches of 
irregular and indistinct outline are smaller and more densely gath- 
ered in the middle area, especially above the pharynx, but more 
sprinkled towards the margin of the body (Plate III, Fig. 8). Above 
the brain the pigmentation is not remarkably poorer than in the 
surrounding area, or at least the difference is not very noticeable. 
The tentacles are, on the other hånd, pigment-free. 
The under surface of the animal (Plate III, Fig. 7) lacks, of 
