Acrania (z33)
Historical document, translated for reference. It reflects medical knowledge of the 1920s–30s and is not medical advice.
Summary
This 1930s encyclopedia article defines Acrania as a subphylum of chordates, commonly known as acraniates or lancelets, which lack a true skull, vertebral column, and brain. It highlights their evolutionary significance in comparative vertebrate morphology, focusing on Amphioxus lanceolatus.
Encyclopedia entry (1928–1936)
ACRANIA (from Greek a- negative particle and kranion - skull), acraniates, a subphylum of the chordates; in their organization they present much in common with vertebrates, although they possess not only no skull and vertebral column, but also no brain, instead of which there is only an expansion at the anterior end of the spinal cord. The morphology of acraniates contributes much to clarifying the evolution of vertebrate animals; the object of study is their most widespread representative, Amphioxus (see) lanceolatus.
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Cite this page
“Acrania (z33).” Soviet Medical Encyclopedia. English translation of Bolshaya Meditsinskaya Entsiklopediya, 1st ed. (Moscow, 1928–1936), ed. N. A. Semashko. https://sovietmedicalencyclopedia.pages.dev/article/acrania/