The gross anatomy of the blood vascular system of the Eel <i>Anguilla anguilla.</i>

Abstract

Summary. The gross anatomy of the Eel's circulation is described. The following points are noted:–.( a ) the simplification of the cranial circulation owing to the absence of a pseudobranch; ( b ) the existence of forked ventral ends to the efferent branchials; ( c ) the origin of the coronary arteries; ( d ) the distribution of the gut arteries; ( e ) the unusual vascular supply of the pneumatic duct and gas bladder and its possible significance; ( f ) the tendency to asymmetry especially in the venous system. It is concluded that the Eel's vascular system is relatively unspecialized though the absence of a pseudobranch and the presence of the pneumatie duct capillary network must be regarded as specialized features. This work was carried out during the tenure of a maintenance grant from the Department of Scientific and Industrial Research