tween radial canals 5. and 1. Figs .9.12,13, and 14. 

 hip, 1-2 ,2-3, 3-4 ,4-5, and ipax.5-1. These five pouches 

 are the rudiments cf the outer perihaemal ring which 

 will be more fully considered in the succeding stages. 



The stomach after being entirely cut off from 

 the hypogastric enterocoele v. r as drawn forward during 

 the rotation of the hydroeoele and the oesophagus 

 was carried in the opposite direction so that in 

 "B" the stomach lie- almost directly over the oe- 

 sophagus .Figs .9. and 13. oe, and s. The partition, 

 which in"C" separated the cavities of these tv. r o 

 structures, has disappeared in "B" and the oesopha- 

 geal cavity opens into that cf the stomach .There 

 is present then in "B" the definitive alimentary ca- 

 nal cf the adult ophiurid. 



The 1 cellular mass', which in "B"and "C" was heing 

 divided into two parte by the constriction separat- 

 ing the archenteron into enterocoele and stomach, 

 is to be found.in sections of "D" in the cavities 

 of both the above structures .Figs .11 ,12, 13, and 14, cp. 



Lying immediately above, or aboral to, the stom- 

 ach, lies the epigastric enterocoele. It has enlarg- 

 ed considerbly during the interval between "C" and "B" 



