CHROMODORIS ZEBRA HEILPRIN 



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their contents into the lateral blood vessels which enter the auricle 

 at its posterior angles. It is probable that, as occurs in other 

 forms, the entire primary body cavity surrounding the various 

 organs is filled with the blood fluid and that this is collected and 

 aerated in the branchiae, from which it passes directly into the 

 middle portion of the auricle through the posterior median blood 

 vessel of the auricle. 



en. 



Fig. 4 Heart, blood gland and some of the more important blood vessels. 

 aurl., auricle; gl.sng., blood gland; v., ventricle; va.sng.buc, blood vessel to buccal 

 mass; va.sng.gen., blood vessel to genitalia. 



The blood gland (fig. 4, gl.sng.) is an irregular leaf-like mass 

 made up of very small round cells. It lies immediately above the 

 central nervous system and has an antero-posterior diameter of 

 7 mm. and a lateral diameter of 5 mm. 



There are from 12 to 14 branchiae in the branchial circle. Each 

 branchia is provided with an afferent and an efferent blood vessel, 

 which carry the blood respectively to and from the branchiae. 



