A Review of the “Open” and “Closed” Circulatory Systems: New Terminology for Complex Invertebrate Circulatory Systems in Light of Current Findings

<table>The annelid
circulatory system, though a low pressure system, contains contractile vessels
for pumps and a highly branched vascular system. It lacks an endothelial
lining. (a) Longitudinal section, (b) cross-section of the earthworm (<i>Lumbricus</i>)
(adapted from R. C. Brusca and G. J. Brusca, [<a href="/journals/ijz/2009/301284/#B8">4</a>]).</table>

International Journal of Zoology

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Figure 2

Figure 2: A Review of the “Open” and “Closed” Circulatory Systems: New Terminology for Complex Invertebrate Circulatory Systems in Light of Current Findings 

Figure 2 | A Review of the “Open” and “Closed” Circulatory Systems: New Terminology for Complex Invertebrate Circulatory Systems in Light of Current Findings 