Fig 
Fig. 
Fig. 
Fig. 
Fig. 
CASTLE, 
- Ciona intestinalis. 
PLATE III. 
All Figures represent sections; magnification, 560 diameters. 
Conjugation of pronuclei viewed in the direction of the equator of the 
first cleavage spindle. (Cf. Plate I. Fig. 6.) 
First cleavage spindle. 
First cleavage nearly completed. Each of the newly formed nuclei is 
made up of two vesicles as yet incompletely fused. 
Section through one of the cells of a 2-cell stage, parallel to median plane 
of the embryo. 
Section from the same series as Fig. 16 through one of the two cells, near 
the median plane of the embryo. x, finely granular protoplasm, which 
marks the posterior-ventral side of embryo (cf. Plate VIII. Fig. 45, x), 
and is traceab!e up to the larval stage. 
Section through an 8-cell stage parallel to median plane of the embryo. 
