PLATE 1 



EXPLANATION OF FIGURES 



21 Left lateral view of a wax reconstruction of the left suprapericardial body 

 of an embryo 28 mm. long (H. E. C. 1357). X 125. The attached pharyngeal 

 epithelium is shown in part. 



22 Left lateral view of a wax reconstruction of the left suprapericardial body 

 of an embryo 37 mm. in length (H. E. C. 363). X 125. 



23 Left lateral (medial) view of a wax reconstruction of the right supraperi- 

 cardial body of an embryo 47.3 mm. long (S. C. 11). X 125. 



24 Left lateral view of a wax reconstruction of the left suprapericardial body 

 of an embryo 47.3 mm. long (S. C. 11). X 125. The elements A, B, and C, rep- 

 resent the early connecting-stalk; the element D the ventral vesicle. 



25 Left lateral view of a wax reconstruction of a portion of the left supraperi- 

 cardial body of an adult showing its connection with the pharynx through a true 

 duct. X 30. 



26 Left lateral view of a wax reconstruction of the left suprapericardial body 

 of an embryo 95 mm. long (H. E. C. 1882). X 125. 



412 



