The lowest bristles are still more slender (Plate XXXV, fig. 24 a), and many present
a remnant of the pilose coat at the tip, as in the figure. Posteriorly the hastate
condition is marked (Plate XXXVI, fig. 19).
The second and third feet thus differ from the succeeding in having, instead of the
most ventral series just described, a tuft of somewhat slender pinnate bristles (Plate
XXXVI, fig. 17), the pinnae in the third foot being stronger. These probably represent
the primitive bristles.
The slender feet at the posterior end of the body have ventrally a. series of
elongated bristles, with short spikes somewhat alternately arranged distally (Plate
XXXVI, fig. 3). They end in a tapering tip. These bristles are further modifications of
the pinnate forms.
The warts on the feet, and near their bases are often coloured dark brown or
blackish, and in many also the general surface of the feet.
A small specimen (1£ inches) procured in Cromarty Frith on August 31st had the
bases of two anterior feet fixed together by an elongated, hard, brownish mass, which
was sunk in the tissues, and another circular patch was near. Only an indefinite
granular structure was visible with the microscope, and the structure was more or less
calcareous, giving off gas on the addition of hydrochloric acid. Both were firmly fixed
in the skin.
Reproductive Organs.—Pallas represented the ova of Aphrodita as originating in the
perivisceral fluid itself, a supposition in th e same category as the notion that the glandular
wall of the alimentary canal in the Oligochastes gives rise~to the perivisceral corpuscles.
At Naples Lo Bianco found the males emitting sperm in March. At St. Andrews
specimens have abundant ova in May. The larvae have not been seen.
The direction of the papillae of the segmental organ would apparently send the
reproductive elements dorsally under the felt, and as streams of water are constantly
pouring through this space, the ova would be duly impregnated and aerated. The
sperm would likewise be rapidly distributed all around.
A specimen off Howth, Ireland, showed Loxosomae, and a delicate creeping Cain-
panularian on the ventral surface and between the feet. In one from St. Andrews
Foraminifera were thickly dotted over the ventral surface along with Balani (small),
great numbers of stalked Infusorians, and an occasional very young mussel.
In the felt of the dorsum many small marine organisms are entangled, from algae to
mussels, Annelids, crustaceans, sponges, zoophytes, polyzoa, and spines of Echinoderms.
Small preserved specimens are proportionally broader than the adult, and taper much
more rapidly at either end. Such probably is partly due to rigid contraction. They
occur from an inch downward in the stomach of the haddock, and occasionally in the
stomach of the dab.
Delle Chiaje1 records a nematode as a parasite in the dorsal felt, and as having a
translucent body and a filiform tail. This is like Phoronis in the test of Oerianthns
from Australia. The nematode, however, may only have lodged, temporarily.
The species lives fairly in confinement, but as a rule not for a long time. The
difficulty of supplying it with suitable nourishment—for mud in a confined tank soon
1 e Descrizione,’ vol. iii, p. 138.
becomes odoriferous—is probably the cause of its mortality. In its native sites it seems
to make its way in the. mud and sandy mud by aid of its powerful ventral bristles,
whilst its back is laved by currents of sea water under the felt which protects this somewhat
delicate surface from direct contact with its surroundings. I t appears to be a
limivorous form, pursuing its work in the depths of the sea, where its beautifully iridescent
hairs can be seen by few admirers. I t does not always follow that the reasons for
gorgeous apparel or brilliant phosphorescence lend themselves readily to the inquirer.
The smallest example in my collection was procured on the bottom by Dr. Alford
Anderson on board the ‘ Garland,’ on the 9th August, 1888, on the trawling grounds
near the Bell Rock. I t measures 3’5 mm. in spirit. The dorsum is covered with sandy
mud in which are a few fine hairs. The ventral surface forms a proportionally broader
area than in the adult. There are nineteen segments besides the pro- and peristomium,
and there are no . signs of the lustrous hairs, yet the larger bristles of the ,feet are
prominent, though few in number. Each foot has superiorly in the ventral division a
long hastate bristle slightly bent downwards at the extremity, the hastate region having
a coating of fine agglutinated hairs which project beyond the tip. One or two shorter
forms of the same type occur in the next row, the larger- having a similar though less
developed terminal coating. The third series of two smaller bristles has smooth hastate
tips. The spine has a long free point. The dorsal felt is already formed as a dense
interlacing series of fibres, which entangle minute particles of mud and sand. The
dorsal spines are still comparatively short and pale, and do not project beyond the felt
and mud of the sides.
The soberly tinted young form is thus a contrast to the adult in the colour of the
bristles, spines, and hairs. Its hues coincide with the surrounding sandy mud.
Baster’s account (1765) of this species is, on the whole, careful and characteristic, the
arrangement of the ventral bristles and even their number having received attention.
His structural remarks are also interesting, and he found the male and female elements
in June. His figures are fairly accurate.
Rondelet and Swammerdam called the sea-mouse Physalus, while Bartholinus termed
it the golden worm. Seba, Molyneux, and Barrelier, again, named it. Et'uca sive Scolo-
pendra marina. Swammerdam was of opinion that it deserved a place near the sea-
urchins, probably from the prominence of its spines.
Pallas’s description of the external and internal structure is excellent. He had not,
however, seen one seven inches long, as Baster reports. He describes the muscular bands,
the perivisceral fluid, the digestive system, and the stomach (ventriculus), which the
Belgian fishermen call mentulam Aphroditeet and eat it boiled—a poor kind of nourishment
Cuvier afterwards thought. It somewhat resembles the human uterus, he says,
with its os. He is of opinion that the scales are not branchiae, but that fourteen pairs of
sacculate bilobate organs (the dorsal fimbriated papillae) are. He mentions the pinnate
condition of the intestine, figuring the lateral caeca, and describing their attachment to
the “ integument.” He thinks that Redi’s view of the insertion of the caeca in dorsal
sacs will not bear scrutiny. The caeca communicate with the median gut freely, and
chyme enters and is absorbed,—indeed, he saw particles of algae in them, but nothing
in the ventriculus or oesophagus. He corrects Redi’s notion that the nerve-cord and its
34