leted and
rendered permanent in the tubular funnel of Dibranchiata. The
epipodial nature of the funnel is well seen in young embryos, in which
this organ is situated laterally and posteriorly between the mantle
and the foot.

[Illustration: FIG. 5.--View of the postero-ventral surface of a male
Pearly Nautilus, the mantle-skirt (c) being completely reflected so as
to show the inner wall of the sub-pallial chamber, and the four
ctenidia and the foot cut short (drawn from nature by A.G. Bourne).
pe, Penis, being the enlarged termination of the right spermatic duct;
l.sp, aperture of the rudimentary left spermatic duct (pyriform sac
of Owen). Other letters as in fig. 4.]

The lobes of the fore-foot of _Nautilus_ and of the other Cephalopoda
require further description. It has been doubted whether these lobes
were rightly referred (by T.H. Huxley) to the fore-foot, and it has
been maintained by some zoologists (H. Grenadier, H. von Jhering)
that they are truly processes of the head. It appears to be impossible
to doubt that the lobes in question are the fore-portion of the foot,
when their development is examined (see fig. 35), further, when the
fact is considered that they are innervated by the pedal ganglion. The
fore-foot of _Nautilus_ completely surrounds the buccal cone (fig. 6,
e), so as to present an appearance with its expanded tentacles similar
to that of the disk of a sea-anemone (_Actinia_). A.G. Bourne, of
University College, prepared from actual specimens the drawings of
this part in the male and female _Nautilus_ reproduced in fig. 6, and
restored the parts to their natural form when expanded. The drawings
show very strikingly the difference between male and female. In the
females (lower figure), we observe in the centre of the disk the
buccal cone e carrying the beak-like pair of jaws which project from
the finely papillate buccal membrane. Three tentaculiferous lobes of
the fore-foot are in immediate contact with this buccal cone; they are
the right and left (c, c) inner lobes, and the inferior inner lobe
(d)--called inferior because it really lies ventralwards of the mouth.
This inner inferior lobe is clearly a double one, representing a right
and left inner inferior lobe fused into one. A lamellated organ on its
surface, known as Owen's organ, probably olfactory in function (n),
marks the separation of the constituent halves of this d