8 
it consists of the conjunction of the sheaths of four tentacles ; three 
of those tentacles are placed on a common flat expansion ; the fourth 
is contained in a separate slip, placed beneath the three other tenta- 
cles. At the left side, instead of this external labial processus, there 
was a great conoid body, the length of which was nearly 2} inches; this 
part was laterally compressed ; at the basis its measure from the dor- 
sal to the ventral side was found to be 1 inch 10 lines ; from the right 
to the left side only 1 inch. This part was proved to me by dissect- 
ing it to be formed by the union of four unusually developed tenta- 
cular slips, one of which was shorter and more free, the three other 
chiefly composing the singular body. This part occupied a great 
space in the interior of the circle, which was formed by the external 
tentaculiferous digitations of the head, and perhaps its great deve- 
lopment may have been the cause of the more imperfect condition of 
the other three labial processes. 
I regret that this specimen was in a bad state of preservation ; its 
abdominal sac being dilacerated and the viscera destroyed by mace- 
ration. Hence I am not able to give a description of the male organs 
of generation, but that the specimen was a male seems to me unques- 
tionable. At the same place where in other specimens the vulva ad- 
heres to the ground of the branchial cavity, was a short conic part, 
evidently the penis, somewhat bent at the basis towards the ventral 
side, having an obtuse and perforated top. A very narrow canal was 
found to go from this aperture to the root of the penis, and to expand 
there in a pouch, of a firm parchment-like texture. This bladder 
contaimed a conglobate tube of a brown colour, having a little more 
than | line in diameter. The length of this tube could not be deter- 
mined, because, by any attempt to unravel it, it broke into pieces. 
Microscopic investigation proved that this tube was formed by two 
membranes, the external transparent, the inner thicker, coloured, 
brittle, and offering circular stripes or fibres. In the interior of the 
tube there was a thread or band, coiled up in a spire with close cir- 
cumvolutions, like the spiral fibre of the trachee of insects. This 
fibre was not of exactly equal broadness in its whole extent; its 
broadest parts had a diameter of nearly 1-48th ofa line. This fibre 
seemed composed of an external transparent membrane, including an 
internal part of a yellowish brown colour. Between the fibre and the 
tube containing it were observed several free microscopic parts ; some 
greater, of a brown colour, oblong or navicular ; some smaller, unco- 
loured, and still of different size. How different this conglobated 
tube, contained in the spermatic vesicle, may be from the Needham- 
machines or spermatophores of other Cephalopods, I still believe that 
we ought to consider it as a similar sperma-containing apparatus. It 
seems highly desirable that a travelling naturalist may have the op- 
portunity of observing the male Nautilus in a recent state. 
Imperfect as they are, I trust those last observations to be still of 
some interest for comparative anatomy, as giving the first account of 
that which seems now to be the chief desideratum in our knowledge of 
the Nautilus, the disposition and structure of the male generative ap- 
paratus. 
