INNERVATION OF CERATA OF SOME NUDIBRANCHIATA. 551 
and 18) contain ova and spermatozoa in various stages of de- 
velopment. In most cases single lobes are not hermaphrodite, 
but occasionally both ova and developing spermatozoa are to be 
found in the same lobe. In fig. 18 the upper lobe is a purely 
female one and the lower is entirely male, while the small piece 
of a third seen at the left side contains large and small ova and 
also spermatic cells. 
Glands are very abundant in the integument of this minute 
species. Fig. 17 shows the large mass of ovate glands above 
the foot, and the numerous small glands scattered all over the 
surface of the cerata; these latter are seen more highly magni- 
fied in figs. 18 and 19. The connection between the hepatic 
ceca in the cerata and the median portion of the liver in the 
body is seen in fig. 17 on the right side, and the opening of the 
hepatic czecum into the cnidophorous sac at the apex of the 
ceras is shown in fig. 19. This opening is surrounded by 
muscle-fibres which encircle the lower half of the cnidophorous 
sac. The cnidocysts are large and distinctly nucleated 
(Pl. XX XIII, fig. 19, cz. ¢.), and the cnida are of elongated 
ellipsoidal form. 
Kouis (FAcELINA). 
In Eolis (or Facelina) coronata we find that, as Alder 
and Hancock showed long ago for EKolis papillosa, the chief 
nerves to the cerata arise from the pedal ganglia ; but there is 
also, on one side at least, a smaller accessory epipodial nerve 
which is pleural in origin. 
The numerous large cerata arise from the body in Facelina 
coronatainclumps (Pl. XXXIV, figs. 28 and 32). This is espe- 
cially well shown in fig. 28, where on the left side of the figure 
the section shows a large basal projection from the body common 
to half a dozen cerata. In this basal mass we find muscle- 
bundles and connective tissue, the ducts from the hepatic ceca, 
and the epipodial nerves going to the cerata. This basal region 
of a clump of cerata is separated off from the body proper by a 
line of longitudinal and oblique muscle-fibres (Pl. XXXIV, 
figs. 28 and 31, musc.), through which the nerves have to pass. 
