FIG. 20. HypolnjtltAus call/codes. G, nerve ganglion ; H, 

 heart ; JNI, the position of the atriopore. The large open- 

 ing on the upper side is the mouth. (From a drawing by 

 Professor Moseley in Herdman V Tunicata of the "CrmJ- 

 Expedition.') 



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lenger 



