DR, ALLMAN ON THE ANATOMY AND PHYSIOLOGY OF CORDYLOPHORA. 383 
Fig. 8 . Cells liberated by pressure from the endoderm of the stomach. They are 
filled with smaller cells, which contain coloured granules, and seem to 
have been originally contained within the proper cells of the endoderm. 
a. Nuclei of contained cells distinct. 
h. Nuclei concealed by the coloured granules. 
Fig. 9. Portion of a tentacle near its root, to show its structure. 
a. Ectoderm with thread-cells. 
b. Endoderm, its cells containing coloured granules. 
c. Muscular fibres. 
Fig. 10 . Cells containing secondary cells with granular contents from the endoderm, 
when covered by the polypary. 
*** In figs. 11-14 the same letters are used to indicate corresponding 
portions of structure, viz. a. Diverticulum from the coenosarc. h. Ex- 
ternal investment of the reproductive capsule continued from the 
polypary. c. Cellular sac. d. Ramified canals, e. Structureless sac 
secreted on the outside of the cellular sac. 
Fig. 11 . Reproductive capsule — very early stage. 
Fig. 12 . The same— more advanced stage; the cellular sac and ramified canals are 
now visible. 
Fig. 13. Ideal longitudinal section of a reproductive capsule of about the same 
period as fig. 12 ; showing the relation of the ramified canals to the diver- 
ticulum and cellular sac, and the presence of a delicate structureless sac 
which has been secreted on the outside of the cellular sac. 
lig. 14. Repioductive capsule in a more advanced stage ; the ova are now visible in 
its interior. 
Fig. 15. Reproductive capsule still further advanced ; the cellular sac and ramified 
canals have disappeared, and the ova are now seen lying upon the extremity 
of the divei ticulum, and immediately included within the structureless sac 
which had been formed upon the outside of the cellular sac. 
Fig. 16. A more magnified view of an ovum from fig. 15; the germinal vesicle has 
disappeared, and the segmentation of the vitellus has converted the ovum 
into a mulberry-like mass. 
Fig. 17 . A capsule still further advanced; the mulberry-like condition has disappeared, 
and the ova have begun to elongate themselves. 
Fig. 18. A capsule in a still more advanced stage; the ova have become still more 
elongated, and they now present a swarming motion in the interior of the 
capsule. 
Fig, 19. leimination of the intra-capsular life of the embryo ; the enclosing sacs have 
become ruptured, and the embryos are escaping in the form of free ciliated 
infusoria. 
Fig. 20 . Embryo just after its escape from the capsule, more highly magnified; it 
presents an internal closed cavity with ectoderm and endoderm. 
MDcccLiii. 3 E 
