546 W. A. HERDMAN AND J. A. CLUBB. 
the nerve, and running upwards dorsally into one of the two 
large lobes or projections on the ridge (see Pl. XXXII, fig. 3, 
ep. n.’), while the main nerve continues its course backwards in 
the body-wall at the base, giving off small branches, which are 
distributed to the ridge above. The first large dorsal or ceratal 
branch from the main nerve is found in the anterior part of 
the branchial region, and is therefore nearly in the middle of 
the length of the body. Our epipodial nerve is probably nerve 7 
of Alder and Hancock’s Fam. I, pl. xvii, fig. 12, arising from 
the “ branchial” ganglia, and going to the skin of the back. 
Figs. 2 and 3 on Pl. XXXII incidentally show some other 
points, especially, in fig. 2, the cartilages and muscles of the 
odontophore (cart., m.) and scattered teeth of the radula (7.), 
the glands of the foot (f) the blood-spaces of the body-wall 
(6. s.), and the reproductive vestibule (7. a.) ; and in fig. 3 
the ovo-testis (0. ¢.), the liver (/.), the branchie (d7.) with 
their blood-spaces, and the structure of a ceras with its large 
unicellular glands in the ectoderm. 
ANCULA. 
In Ancula cristata the pleural ganglia are distinct from 
the cerebral (Pl. XXXII, figs. 4, 5, and 7). 
In a specimen cut into about 500 sections we find in about 
the 106th section or so from the anterior end six distinct 
ganglia (the cerebral, pleural, and pedal pairs) surrounding 
the esophagus (Pl. XXXII, figs. 4 and 5). A few sections 
further back the cerebrals disappear, and then (in the 113th 
section, Pl. XXXII, fig. 6) the epipodial nerves are found 
arising from the dorsal edge of the pleural ganglia. They run 
dorsally and outwards and then posteriorly, lying free in the 
body-cavity. 
Soon after leaving the ganglion each epipodial nerve gives 
off its first branch dorsally. This branch enters the mesoderm 
of the dorsal body-wall, and can be traced back through over 
1 In this same figure Alder and Hancock show on the left side a small 
accessory nerve (8) to the side of the body, arising from the pedal 
ganglion. 
