come about ten colourless dagger-like teetb (Fig. 7 b), with from four to ten fairly regular
denticles on either side, the number of denticles increasing as the teeth are further from
the rhachis. After this the teeth, as one goes outwards, become larger, yellower, hollowed,
and somewhat spoon-shaped, bearing on either side at least twenty-five denticles, which
are shorter and blunter than those of the middle teeth. The outermost teeth of all are
somewhat smaller.
The internal organs are not easy to unravel, all the tissues being very thin, soft,
and easily torn. The oesophagus leads into a round stomach, which gives off branches,
apparently one on either side, and is prolonged posteriorly in a diverticulum reaching
nearly to the end of the body. On this lie the liver and the hermaphrodite gland, both of
which are yellowish and difficult to separate from one another. The whole mass is
surrounded by a network of transparent tubes, which seem to represent the kidney.
The dorsal papillm are hollow and communicate with the interior of the body, but I could
not satisfactorily demonstrate the existence of branches of the liver in them (cf. what
Trinchese says about L. eisigii). If such exist, they are represented by flocculent masses
of no very definite shape, composed of reddish cells. In the unusually pale and
transparent specimen represented in Figs. 7 and 8 they are seen to extend into the lower
parts of the large papillae and rhinophore sheaths but not into the tips. The mucus and
albumen glands are large; the ampulla of the hermaphrodite gland is long and thick; the
vas deferens thinner and coiled; the penis conical and unarmed; the spermatotheca
small and roundish.
If any valid distinction can be drawn between L. genei and L. eisigii, this animal
should probably be referred to the latter in virtue of the shape of the papillae and the
apparent absence of hepatic diverticula in them. But I do not think that the two species
are really distinct.
LOMANOTUS MARMORATUS A. & H.
Four living specimens (A) examined at Plymouth in April, 1905, were about 9 mm.
long and 2 mm. broad. The ground colour of the living animals is .yellowish white, but
largely covered with irregular markings of different shades of brown and olive, and also
with small sandy dots. The colour is darkest at the sides and lighter in the centre of
the back. The tips of the cerata are whitish; the hepatic diverticula within them
yellowish brown.
The anterior margin of the foot is cleft and indented, with strongly hooked corners.
The veil is not large, with four processes, two on each side, which are somewhat bulbous
at the tip. The rhinophore sheaths are rather tall for the size of the animal, being about
2 mm. high, and bear four or five processes, the number not being always the same on the
right,and left sheaths. In one specimen one sheath is entirely smooth. The dorsal margin
starts from the rhinophore sheath ; it makes four not very distinct undulations and bears
about twenty-two papillae, most of which, especially the taller ones, are carried vertically,
though some of the smaller ones point sidewards. The taller papillae bear a distinct bulb
under the pointed tip, but in the smaller ones the bulb is less developed. Four of the
papillae are distinctly larger than the rest, and, roughly speaking, mark the divisions
between the undulations. The third of these larger papillae is the tallest of all and is
about 2 mm. high.
Another specimen (B), which was about 7 mm. long when at rest and 8 mm. when
crawling, was brownish white, with yellowish-brown mottlings down the centre of the
back and deep purplish-brown mottlings on the cerata. The other external characters
are much as in the specimens already described, but the papillae are not so long and there
are only obscure indications of the subterminal bulb. The dorsal margin is more clearly
a web connecting the papillae. The rhinophore sheaths bear five processes each.
Three other specimens of about the same size were so macerated that nothing could
be done with them except to examine the buccal parts.
The jaws and radula are much the same in all eight specimens. The jaws are not
denticulate, but near the edge is a mosaic formed of tile-like prominences with denticles
on their anterior margin. The radula is very irregular in appearance and could not be
laid out straight in any specimen. There is a wide naked rhachis bearing folds, and on
each side of the rhachis are fifteen to twenty rows of teeth, each containing eight to ten
teeth on either side. More could not be made out with certainty. The teeth are longer
than in Alder and Hancock’s and Bergh’s plates, and more uniform. They are daggershaped,
but slightly bent at the end, bearing at least twelve denticles on either side and
perhaps considerably more, but the denticles are hard to see, even with a high power.
The' innermost are slightly shorter and stouter; the outermost longer and thinner.
The animals are very delicate. They die in captivity without apparent cause, and
the body becomes decayed and macerated very rapidly.
This form, especially the specimen called B, approaches the L. marmoratus of Alder
and Hancock sufficiently near to bear the name. Their plate (Eumenis marmoratd, Fam.
8, pi. 1, a) contains one of the few inaccuracies to be found in their works, inasmuch as
it represents the dorsal margin as continuous with the oral veil, not as starting from the
rhinophores. But in a preliminary study for the figure preserved in a bound volume
of Alder’s drawings, belonging to the Hancock Museum at Newcastle-on-Tyne, the
disposition of the parts is somewhat indistinct, and it is probable that it was intended
to represent the dorsal margin as starting from the rhinophores. When this study was
copied for the plate as published, the artists themselves may have misinterpreted their
earlier and rather indistinct drawing.
Colgan (l. c.) not only regards L. marmoratus as synonymous with L. genei, but
wishes to give the former name priority on the ground that Vér any used the binominal
Latin name first in 1846, and in 1844 simply said it was a species of Lomanotus
“ dedicata al Prof. Gêné.” But the identity of the two forms is not sufficiently certain to
warrant the use of one name for both, and, apart from that, if the rules are to be applied
with such severity to Vérany, it might be objected that Alder and Hancock’s figure
represents a differently formed animal and that L. marmoratus must have that conformation.
I do not however think that we should insist that the continuity of the dorsal
margin and oral veil is really a character of L. marmoratus A. and H,