G7 



course, bends around the adauctor-, and divia^s into paired 

 pallial arteries which supj^ly the posterior part oi" the 

 body. This is the posterior aorta. TiiQ other, the ante- 

 rior aorta also runs forwards a short distance, but soon 

 breaks up in the viiiceral mass, 



I have gone into details in describing the aortae , 

 because the posterior aorta is described as fused with the 

 anterior in Teredo. This observation was first made by 

 Grobben (5) , v/ho described as aorta a part of the ventri- 

 cle which is distinctlj'- muscular and contractile. The 

 part that should have been described as aorta he has not 

 figured at all. Menegaux has also maintained that the t\'ro 

 aortae are fused (11). Unfortunately, neither of these 

 v/orkers names the species with which he v/orked, but their 

 descriptions of other parts are so faulty as to indicate 

 that there is little doubt that they have been in error in 

 this regard. 



