377 
of Edinburgh, Session 1876-77. 
slender muscle passing from the outer border of the ventral longi- 
tudinal. In many sections a neural canal is seen somewhat above 
the middle of the area. A muscle passes from the bristle-tuft up- 
ward in a slanting direction through each pedicle to the raphe be- 
low the nerve. In Travisia Forbesii , Johnst., the nerve-trunks are 
situated between, and somewhat above, the insertions of the 
oblique muscle. Externally are the circular coat, a translucent 
basement-tissue, a granular hypoderm, and a very thin cuticle. 
ScALiBREGMiDiE. — In Eumenia Jeffrey sii the cords in the anterior 
region occur toward the inner aspect of the thick layer of trans- 
lucent basement-tissue, below and between the insertions of the 
two long oblique muscles. Toward the middle of the body the 
trunks still indent the basement-tissue, the circular muscular coat 
forming their inner boundary. A series of strong transverse fibres 
occurs at intervals as an arch over the cords. In Scalibregma in- 
flatum, H. B., the cords (in the posterior region) lie below the cir- 
cular muscular fibres, which occur beneath the commissure of the 
oblique in the middle line. Externally are the hypoderm and 
cuticle. 
TELETHUSiE. — In the anterior third of Arenicola marina , L., the 
cords form a comparatively small ovoid mass— clasped by the great 
longitudinal muscles, and connected with the circular coat by a 
narrow granular pedicle. 
Si’H/ERODORiDyE. —While there is a very thick cuticle in Ephesia 
gracilis , H. R., the hypoderm is slightly developed below the 
nerves. The oblique muscles pass from the inferior border of the 
bristle-tufts to the outer margin of the nerve-trunks. 
Chlor,emid,e. — In Trophonia plumosa, 0. F. Muller, the nerves 
lie above the median decussation of the oblique muscles, the cords 
being distinct in the intervals between the ganglia. Externally 
are also the circular coat, a narrow hypoderm and a roughly 
papillose cuticle.* 
CmETOPTERiDiE. — In Chcetopterus norvegicus , Sars., the cords are 
placed wide apart in front, in consonance with the peculiarly 
modified muscular arrangements of the body- wall. They are hypo- 
dermic. By the great increase of the median system of muscles 
* Next the Chlorsemidse Dr Malmgren places the Sternaspididse, but in 
structure Sfcernaspis is Gephyrean. 
