DAVENPORT 
can. comn. 
Cera, Al, 
cn’ph. 
cee. 
ec’drm. 
ga. dv. 
gl. nid. 
gl. pd. 
gn. 
mo, bue. 
ms’drm. 
— Cerata in Xolis. 
PLATE II. 
ABBREVIATIONS. 
Communicating canal. ms’drm.’ Mesoderm lining body wall. 
ete. Cerata of) 1) Il, ete: ms'drm.” Mesoderm lining hepatic 
transverse rows. coecum. 
Cnidophore. nl'cy. Nematocyst, smaller kind. 
Ceecum. nt’cy.’ Developing nematocyst. 
Ectoderm. nt’cy.” Nematocyst, larger kind. 
Stomach. pd. Foot. 
Posterior prolongation pe. ves Penis sac. 
of stomach. rad, Radula. 
Gastric diverticulum. rhn. Rhinophore. 
Nidamental gland. rt. Rectum. 
Foot gland. te. Testis. 
Ganglion (cerebral). ur. Ureter. 
Buccal mass. I, IL, 1., 9, &. Lobes of ovary and 
Mesoderm. testis. 
Figs. 9-11. Three stages in the development of the cerata. Vertical sections 
2, 
As. 
Ns 
Seno 
Gs 
atte 
Saks: 
pa20: 
Longitudinal section of ceras just before formation of external opening of 
enidophore. X 120. 
Transverse section of adult enidophore, showing nematocysts. X 405. 
Bit of transverse section of hepatic ccecum, showing fully formed and 
developing nematocysts in hepatic cells. 405. 
Bit of transverse section of hepatic cecum, showing large nematophore. 
x 405. 
Longitudinal section of young J£olis, inclined about 30° from vertical, 
passing through axis of alimentary tract and first ceras of three trans- 
verse rows. XX 76. 
Enlarged view of the posterior of the two regions marked by asterisks in 
Figure 16, but from a section adjacent to Figure 16, showing parietal 
mesoderm. some of which is about to form that of the youngest trans- 
verse row, and some to give rise to sexual cells, te. 518 
Longitudinal section of young ®olis. Oblique in front, nearly frontal 
behind. Showing repetition of sexual organs and their relation to 
transverse rows of cerata. XX 76. 
