478 MALL. 



DESCRIPTION OF PLATE XXIX. 



Fig. i. External view of the embryo before it was sectioned. Enlarged 20 times. 



Fig. 2. Corrosion preparation of the pericardial and pleuro-peritoneal cavities. 

 Enlarged 44 times. P. pericardial space; A. opening for aorta; V. opening for vein; 

 Z. space over liver ; M. slit for mesentery ; W . B. space for Wolffian body. 



