Fic. 14.—Cross-section of anterior cesophagus to show the difference 
in the development of the chitin and hairs. se., secreting epithelium; 
ch., chitinous layer; p., projecting hairs. 
Fic. 15.—Longitudinal section of cesophageal invagination. ch., chitin; 
e., epithelial layer; m., muscle layer; s., sphincter muscle; ov., ceso- 
phageal valve; me., mesoderm. 
Fic. 16.—Longitudinal section of cesophagus and small cecum. e., epi- 
thelium of stomach; as., active secreting epithelium; mw., muscle wall. 
Fic. 17.—Cross-section of large ventricular cecum. mw., muscle wall; 
se., secreting epithelium; sg., secreted globule. 
Fic. 18—Cross-section of small ventricular cecum. mw., muscle wall; 
se., secreting epithelium; s., secretion thrown off. 
Fic. 19.—Wall of ventricular caecum to show active secretion. 
Fic. 20.—Central cross-section. h., heart; ls., large ventricular cecum; 
ss., small ventricular cecum; a., alimentary canal; f., fat bodies. 
