No. 471] ANATOMY OF ACM.KA T FST f I >/ X A I.I S 183 



side, abutting against the anterior portio 

 is a pellucid triangular space, the jx ri 

 for the most part in the anterior, nearly 

 sac and may in a preserved speeiineit of 

 quite hidden by the generative^ oruan. 

 Such an appearance is, however, an artel 

 of the anterior wall brought about by st 

 the pericardium and abutting against tl 

 of the columellar muscle lies the dorsal j 

 diuni; the ventral part of the organ oec 



The structures thus far 

 made out more satisf actor 

 vessels now to be eininierat 

 tage in a living animal thoi 

 a preserved one. An Aeni 

 to 25° C. until dead or dyi 

 some at least of the mantle 

 sliows clearly the followino 



1. Internal pallial ve- 

 arfrric of Haller), which li 

 muscle and, like it, forms a 



2. Perivisceral vessel, : 



of this I 

 falls int. 



Lithors), which fo 



