PLATE 7 



EXPLANATION OF FI(irRF> 



(Cryptobrancluis allesh(Miicnrti.s) 



Biflironuile-Mcctic-fonnalin fixation. X 4. 



250 Stage 20. Lateral view. 



251 Stage 20. Ventral view of the embryo shown in the preceding figure. 



252 Stage 21. Ventral view. 



253 Stage 21. Lateral view. 



254 Stage 21. Dorsal view of the embi yo shown in the preceding figure. 



255 Stage 21. Ventral view of the embryo sliown in tlie preceding figure. 

 25fi Stage 22. Dorsal view. 



2-57 Statre 22. Ventral view of the embryo shown in the jjreceding figure. 



572 



