160 
THE VOYAGE OF H.M.S. CHALLENGER. 
5. Innervation of the rudimentary eyes of Nymphon robustum, Bell; magnified 94 
diameters. , optic nerves forming the ganglion g; t, oculiferous tubercle ; 
o, rudimentary eyes. 
6. Innervation of the proboscis of Nymphon robustum, Bell; magnified 10 dia- 
meters. The proboscis has been figured as transparent; the mandible and 
the palp of the left side have been cut away. ¢, oculiferous tubercle ; s, supra- 
cesophagal ganglion; c, cesophagal commissures; u, azygous proboscideal 
nerve; p, secondary proboscideal nerves arising from the supracesophageal 
ganglion ; mn, mandibular nerves; p, proboscideal nerves arising from the 
first thoracic ganglion; g, ganglionic bundles; «, small ganglia in the front 
of the proboscis; y, large proboscideal ganglia; a, first proboscideal nerve 
ring ; a@-a! second to fifth proboscideal ring. 
7. Transverse section of cephalothoracic segment of Colossendeis leptorhynchus, 
Hoek (female specimen) ; magnified 10 diameters. s, supracesophageal gan- 
glion ; ¢, first thoracic ganglion ; @, cesophagus ; c, cesophageal commissures ; 
2, rudimentary cceca of the intestine ; m, and mm’, muscle-bundles ; m, passing 
through the cesophageal commissures. 
8. Part of the ganghonie bundle in the proboscis of Nymphon robustum, Bell; 
magnified 94 diameters. wu, g, a, a’, a”, x, and y, as in fig. 6. 
9, Transverse section of the proboscis of Nymphon robustum, Bell; magnified 23 
diameters. I., II., and III. the three chitinous plates limiting the cesophageal 
cavity ; t, transverse muscles ; /, longitudinal muscle-bundles ; @, proboscideal 
ring; g, ganglion of the ganglionic bundle; p, the three main proboscideal 
nerves on transverse section. 
10. One of the ganglia on the inner surface of the integument of Colossendeis pro- 
boscidea, Sab. (sp.); magnified 272 diameters. c, integumentary cavities ; 
b, blood-corpuscles. 
11. Six sections through the supracesophageal and first thoracic ganglia of Nym- 
phon strémz, Kroyer ; magnified 56 diameters. s, supracesophageal ganglion ; 
@, cesophagus; ¢, first thoracic ganglion; 2, intestinal ccecum for the 
mandibles; ¢, fibres of connective tissue; 0, optic lobes; 0’, part of the 
optic nerves; m, mandibular lohes; x, azygous lobe of unknown function ; 
co, esophageal commissures ; p, origin of the two main proboscideal nerves ; 
I, origin of the nerves for the ovigerous legs; co’, commissures between the 
first and second thoracic ganglia. 
12. Longitudinal section through the first thoracic ganglia of Nymphon brachy- 
rhynchus, Hoek ; magnified 170 diameters. pv, proboscideal nerves ; pa, part 
of the neurilemma of the palpar nerve ; e, part of the neurilemma of the oviger- 
ous nerve ; c, commissure between this and the second thoracic ganglion. 
