68 F. W. FLATTELY. 
Fic. 4.—Transverse section through A-B in Fig. 7, showing the sensory lips and the 
ciliated epithelium of the gut. 
Fies. 5 and 6.—Sections showing the gradual disappearance of the vestibules and the 
fusion of the sensory flaps with the sides of the pharynx. 
