542 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 
the branchial heart of its side. This slanting course at 
first causes them to run external to the kidneys, but more 
posteriorly they run over the kidney sac (fig. 69), and 
then passing between the ureter and the oviduet—or 
penis—they gain the branchial heart, and finally end in 
the branchial nerve which runs up the fleshy axis of the 
gill (fig. 69, Bl. N.). The visceral nerve swells during its 
course into two ganglia, of which the second is the larger. 
The first is a small oval ganglion, just anterior to the 
ureter. Krom it radiate fine nerves to the oviduct, 
coelomic canal, flask-like division of the coelom, and the 
aorta (fig. 69, g'). Two other fine nerves are given off, 
one running down the surface of the kidney to the wall of 
the genital capsule, while the outer and smaller nerve ends 
in the kidney wall (fig. 69). The second ganglion is 
larger, and is about 3 mm. across (fig. 69, g’). It is 
attached to the cord dorsally, and adheres to the wall of 
the branchial heart. Branches radiate out from its free 
edge, to the walls of the lateral venae cavae, and the 
efferent artery. Several branches are also given off to the 
substance of the branchial heart, and there is a small 
anterior branch which runs to the muscles of the back. 
Two longer branches sink down dorsal to the kidney, and 
end in the back and the genital capsule respectively. 
Beyond this ganglion the nerve may be called the 
branchial nerve. It runs along that side of the gill 
nearest to the visceral mass, just lateral to the afferent 
blood vessel (fig. 69, Bl. V.). It gradually narrows down 
with the decreasing size of the gill, and swells to a 
ganglion at the level of each internal lamella of this organ 
(fig. 69, Bl. g.). Hach ganglion gives off a nerve which 
runs down the gill lamella to which it corresponds, and 
also a second nerve which runs dorsal to the afferent 
vessel, and so reaching the external side of the gill feeds 
