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Fig. I. M. graf fx, n. sp. (Zeiss CC. Oc. i.) Semi-schematic illustration of an ideal transverse section through the anterior
part of the proboscis, showing the tentacular nerve-ring with some of its pertaining nerves. The figure is constructed
from a series of transverse sections, and partly drawn under the Camera-lucida. cm’, cm", cm". Nerves running
to the oesophageal-ring. o.n., o.n. Root of the 4 oesophageal nerves. t.n. Tentacular nerves, n’. Nerves
passing to the walls of the proboscideal canal, m.r. Muscular ring. n.n. Transsected branches of the first pair of
large nerves, n.c. Ganglionic cell pertaining to a parapodial ganglion.
2—7. M. giganteum, n. sp. (Zeiss CC. Oc. 2. Cam.-Inc. Borax-carmine. Picric acid.) Transverse sections at small
intervals, from a series through the proboscis. Fig. 2. In this fig. the dorsal portion of the tentacular nerve-ring
t.r. is visible, tn, tn. Tentacular nerves, n’, n’. Nerves running to the epithelium of the proboscideal canal, m’.
Muscles surrounding the tentacular nerve-ring. in. Muscles under the ectoderm, m.r. Annular muscles surrounding
the proboscideal canal. Fig. 3. The anterior extremity of the muscular bulb is transected. The ventral portion
(■tr.) of the nerve-ring is visible. o.n, o.n. The oesophageal nerves given oft" from the ring. o.e. The sensory
epithelium of the proboscideal canal, in which, are, also, seen ganglionic cells, cm’, cm", cm’". Nerves
connecting the tentacular nerve-ring with the oesophageal-ring. f, /’, /". Fibrillar nerve-cords, communicating with the
nerves cm’, cm", cm"’, and, probably, also with the nerve-cells (nc.). m’, m’. Muscles, occurring in the
connective-tissue between the muscular bulb and the ectoderm. Fig. 5. The nerve-cells are, here, seen to be arranged in
more distinct groups (gr1., gr2., gr3.) especially round the nerves cm’, and cm", f. Transsected nerve. «.Portion of
a nerve running towards the ventral side. Fig 6. The oesophageal ring is, here, seen. On one side are seen,
the ganglionic cells (a.) situated within the neurilemma-sheath. grgr2, gr3. Groups of cells, similar to those in
fig. 5; cells (gr*.) are, also, seen occurring more towards the ventral side. n. Nerve issuing from the oesophageal
ring towards the ventral side; it corresponds to n. in fig. 5- Fig. 7. The cells are, here, more numerous behind
the oesophageal ring, and the groups are less distinct, o.r. Transsected oesophageal ring in which ganglionic cells
are situated.
8. A part of the oesophageal ring, from the proximity of a in fig. 6; more magnified (Zeiss F. Oc. 2. Cam.-luc.)
n.sk. Outer neurilemma-sheath. i.nsJc. Inner neurilemma-sheath. or. The fibrillar mass of the ring. n.c. Ganglionic
cell, whose prolongation can be traced a considerable distance into the fibrillar mass. x. Ganglionic cell in process
of division. n.c . Group of ganglionic cells, n.c". Ganglionic cells situated oa the inner side of the ring. m.b.
Cuticular membrane of the muscular bulb.
9. M graffi, n. sp. (Zeiss F. Oc. 2. Cam.-luc. Hematoxylin.) Lateral section of the oesophageal ring. o.r.
Fibrillar mass of the ring. n.c. Ganglionic cells, situated within the neurilemma-sheath. n.c’. A few of the cells
situated behind the ring. n. Portion-of a nerve issuing from the ring, and directed forwards.
10. M. giganteum, n. sp. (Seibert hom. im. ’/16 Zeiss. Oc. I. Cam.-luc. and reduced to half size. Osmic acid.
Hæmatoxy-lin). Portion ot a horizontal section showing ganglionic cells, situated laterally, behind the oesophageal ring (or.),
n. Nerve projecting forwards. n.c. Unipolar cells whose prolongations are, principally, directed forwards, n.c.
Multipolar cells whose prolongations are, principali)’, directed backwards towards the epithelium of the stomach
(»1. e.). n.s. Nervus sympathicus (?). m.b. Muscular bulb.
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