Mr. H. N. Moseley on Pelagonemertes Rollestoni. 167 
internal body-tissue. When pressure was exerted, the ova 
issued from small corresponding apertures on the ventral 
surface, and the small empty cavities remained. ‘The ova 
were spherical, about *28 millim. in diameter, and appeared 
composed of fat-globules and granular matter. 
The proboscis-sheath, which is wide and capacious, is very 
plamly seen on the dorsal aspect of the body, and dimly 
through the thickness of the body from the ventral aspect. 
Tt has a firm muscular attachment at its orifice; and bundles 
of muscular fibres (apparently retractor) are attached to it here 
on either side (Pl. XV. B. fig..B, 1). The proboscis itself is, 
when retracted, coiled up in the usual manner within its sheath, 
as seen in fig. p. It could unfortunately not be ascertained 
whether the proboscis is armed or not. It was never entirely 
retracted ; but a small portion of it always remained exserted. 
The outer surface of the body of the Nemertine is covered 
with a hyaline, very thin integument, which is thrown into 
numerous folds and wrinkles, which are so arranged along 
certain lines around small spaces nearly free from them as 
to produce on the surface of the body an appearance of a 
series of small polygonal areas separated by fine reticular 
network (fig. D). ‘This condition of the surface was most 
conspicuous about the anterior part of the body; but the 
body was much lacerated by the meshes of the trawl, and 
therefore I cannot say whether the whole integument is 
in this condition in the fresh state or not. The folds and 
plaits in the integument are so sharp that they give the ap- 
pearance, under the microscope, of somewhat spindle-shaped 
bodies with sharply pointed extremities (fig. C, 1, 2,3). At 
first | supposed that these bodies were urticating organs re- 
sembling those of Bipaliwm; but on carefully teasing up a 
portion of the integument with fine needles, and being unable 
to isolate a single one, I concluded that they were mere folds. 
They are, however, of remarkable appearance, from their ex~- 
treme abundance and the manner in which they cross each 
other at all angles. They are well preserved in glycerine 
preparations of the skin hardened in picric acid. 
Beneath the integument is some granular glandular matter. 
Immediately beneath the integument, and in close adherence 
to it, is the muscular tunic, evidently the homologue of the 
cutaneous muscular system of Bepaliwm and other Planarians. 
As in these, the outermost fibres are circular in direction, the 
inner longitudinal. 
The muscular tunic encloses the entire body. It is thin, 
and in the fresh condition of the animal transparent and in- 
conspicuous, but becomes opaque when the animal is hardened 
12* 
