THE RELATION OF CORONARY AND HEPATIC 

 ARTERIES IN THE COMMON GANOIDS 



C. H. DANFORTH 



From (he Department of Anntomy, Washington University Medical School 



FOUR FIGURES 



The regular occurrence of anterior and posterior coronary 

 arteries in several of the Rajidae was definitely recognized by 

 Hyrtl ('58) and T. J. Parker ('84). Subsequent investigations by 

 numerous students of fish morphology have shown that while 

 both sets of these arteries are characteristically present in skates, 

 posterior coronaries do not occur in either the sharks or the tele- 

 osts. This fact has led to the prevailing idea that the posterior 

 coronary artery is peculiar to the Batoidei. Such a vessel, how- 

 ever, has been found in the ganoid, Polyodon, by Allen ('07) and 

 Danforth ('12). 



In the latter paper the writer also pointed out the existence 

 of anterior hepatic arteries arising in connection with the pos- 

 terior coronaries. These anterior hepatic arteries were found to 

 have a relation to the hepatic vein similar, in general, to the rela- 

 tion of posterior hepatics to the portal system. They supply 

 the anterior half of the liver and usually part of the gall bladder, 

 anastomosing here and elsewhere with the posterior hepatic ar- 

 teries. That they may also occur in skates is indicated by a 

 single observation on Raja ocellata where a typical anterior 

 hepatic artery was found extending to the gall bladder. 



The rather unexpected occurrence of posterior coronary ar- 

 teries in Polyodon and the discovery of the anterior hepatics, 

 has prompted the present investigation into the status of these 

 vessels in other ganoids. For this study the crossopterygian 

 Polypterus has not been available, but the laboratory has fur- 

 nished a])imdant material representing at least one genus of each 

 of the remaining four orders of recent ganoids. The following 



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