Castle. — Ciona intestinalis. 



PLATE IX. 



Surface views of preparations ; magnification, 400 diameters. 



Fig. 51. 24-cell stage, ventral view. 



Fig. 52. Tlie same egg, in the same stage, dorsal view (cf. Plate VII. Figs. 43 



and 44). 



Fig. 53. 32-ceU stage, ventral view. 



Fig. 54. The same egg and stage, dorsal view. 



Fig. 55. 46-cell stage, ventral view. 



Fig. 56. The same egg and stage, dorsal view. 



