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Proceedings of the Hoy at Society 
slender pedicle. The oblique muscles bend below the cords to be 
attached to the raphe in the same intervals. Fibres from the 
walls of the alimentary canal also descend to the raphe on each 
side of the trunks. 
Nereids. — In Nereis pelagica , L., the nerve-cords lie rather 
above the attachments of the oblique muscles to the hypodermic 
basement-tissue, the area being continued to the hypoderm by a 
central pedicle. Nereis ( Alitta ) virens , Sars., an epitocous form, 
likewise has the oblique muscles attached on each side of the 
pedicle of the nerve-area, while the vertical are inserted in a 
chitinous arch at the upper and lateral regions. Two well-marked 
longitudinal muscles lie over the cords. Several neural canals 
exist, — viz., two large infero-lateral, a single superior median, and 
a smaller, a little below the latter, on each side. In Nereis diversi- 
color , 0. F. Muller, each cord has a neural canal of considerable 
size towards its inferior border. 
Staurocephalid^e. — The cords are large in Staurocephalus 
rubrovittatus , G-rube, and occur in the somewhat wide interval 
between the ventral attachments of the oblique muscles. Exter- 
nally are the basement-tissue, hypoderm, and cuticle. 
LumbrinereiDjE. — In a Lumbviconereis from Herm, a large 
neural canal exists above the cords, which are carried inward by 
the approximation of the great longitudinal ventral muscles. The 
oblique meet over the neural canal. Externally are basement- 
tissue, hypoderm, and cuticle. The nerves are pressed further 
inward in Notocirrus tricolor , Johnst., the oblique muscles being 
attached to the summit of the nerve-area (laterally), outside the 
fibres forming the special chamber for the vessel. Some fibres 
pass down each side, and cross below the nerve-area. 
The neural canal in the posterior third of Lysidice ninetta, Aud. 
and Ed., is situated toward the ventral border of the ganglia, but 
between the cords in the intervals. The oblique muscles pass 
below the cords. The latter takes place likewise in Palolo viridis , 
Gray. 
EoNiciDiE. — The cords in Marphysa sanguined, Mont., lie be- 
tween the greatly developed longitudinal vential muscles, and 
present the aspect of a margin to the large median neural canal. 
The fibres of the oblique muscles are attached to the upper and 
