Observations on the venous system of three species of Polypterus (Pisces)

Abstract

The venous system of Polypterus exhibits general asymmetry. The features that characterize the venous system of this peculiarly African fish are the possession of many blood sinuses, the segmental drainage of blood, the continuation of the posterior cardinal veins as separated vessels and the occurrence of several anastomozes between the latter. In the absence of any recent comprehensive work on the blood system of this fish, it was thought that investigation of the circulatory system of Polypterus would be valuable. In this paper attention is drawn to Budgettapos;s (1902) original work on a larva of Polypterus senegalus. Contrary to Budgettapos;s findings it is concluded that what he called the “interrenal” vein is in fact the right posterior cardinal vein. It is also found that paired posterior cardinal veins exist in all adults.

On the development of the venous system in Polyptems senegalus (Pisces)

“…Of special interest are those vessels belonging to the hepatic portal system. They have been well described by Abdel Magid (1967) and other information has been contributed by Poll & Deswattines (1967). All these descriptions show clearly that the vena cava has become the most important vessel of the peritoneal cavity.…”

“…The picture that Abdel Magid (1967) has drawn, in which he contends that two posterior cardinals exist in the adult as they did in very young larval forms, has a completely different explanation when one is able to follow the development of the single posterior cardinal vein through different stages.…”

“…Muller (1844) described this vessel in the adult Polypterus as the "liver vein" and Budgett (1901) called it the "abdominal vein". In other descriptions one fkds it called "hepato-pulmonary vein" (Abdel Magid, 1967) and "hepatic vein" (Poll & Deswattines, 1967). Kerr had overlooked its formation in his 1907 publication, but he discovered it later, describing it in 1910.…”

“…No further details on the disposition of the veins of the liver (the hepato-pancreas) in the adult are necessary, because very good descriptions have been given by Abdel Magid (1967) and by Poll & Deswattines (1967).…”

“…Most interesting are the dispositions in the so-called primitive fishes. Abdel Magid (1967) writing on the veins of adult specimens belonging to three species of Polypterus, added to our knowledge of this system. However, some of this author's interpretations conflict with those of previous investigators, who had worked on younger specimens.…”