STRUCTURE AND DEVET.OPMENT OF COEEOIT.ANA. 57 



of the pharynx; the cavities of the two halves make together a cruciate 

 form. Finally, fig. 17 represents a section of a more aboreal region; the 

 stomodaeal wall shows itself in this figure as a set of rings of different 

 sizes placed one inside of another. Of the three rings in all, both of 

 the two outer rings are the wall of the internal half of the pharynx 

 folded upon itself, while the third and innermost ring is the oesophageal 

 wall. 



The stomodaeum is clothed with an epithelium which consists of 

 ciliated cells and gland cells. Of the gland cells, both kinds, viz., the 

 granular and the clear, may be met with in nearly the same number. 

 The cihated cell is developed much better in the oesophageal wall than 

 in the pharyngeal, whereas, the gland cell is by far commoner in the 

 latter than in the former. The wall of the pharynx measures about 15 ft 

 in the thickest part near the mouth aperture. 



The oesophagus communicates dorsally into the infundibulum by 

 a rather small roundish aperture. The infundibulum (PI. 3, fig. 9, PI. /> 

 figs. 13, 16; /') is a relatively spacious chamber of a cup-like shape, 

 situated directly beneath the aboral sense-organ and between the paired 

 tentacular apparatuses. It is nearly as wide in the transverse as in the 

 sagittal direction, and is divided laterally, though not very sharply, into 

 two halves placed one on each side of the transverse plane, by the internal 

 end of the tentacle-root produced for some distance into the cavity (PI. 

 7, fig. 16; i). The infundibulum is lined on all sides with endodermal 

 cells, of which the cells clothing the roof are fairly low, as compared 

 with those lining other parts. The cells may be vacuolated and contain 

 food particles. 



The lateral halves of the infundibulum give rise each to an 

 excretory canal which ascends along the sagittal side of the sense-organ 

 and opens to the exterior right at the outside of the crest-like prominence 

 described above (PI. 3, fig. y, PI. 7, %• I5; ex. c). This canal unlike 

 that of ordinary ctenophores is not divided before the opening. It is 

 lined with the direct continuation of the epithelium of the infundibular 

 wall. From each half of the infundibulum, towards the oral direction, 

 two canals of a relatively broad calibre are given out; they descend 

 through the parenchyme tissue that occupies the interradial parts of 

 the body, and terminate blindly at the level directly above the oral 

 aperture. The canals keep a close attachment to the tentacle-bases 

 throughout their length, with their external wall closely attached to 

 the internal margin of the latter. There the canalar wall is made up 



