The second well-developed actinost is below the vertebra supporting the subcaudal blood-vessels, but that is not so strong proximally as the first; the ribs are not directed downwards, but backwards, and are entirely separated from each other.
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Actinost — Ac tin*ost, n. [Gr. ?, ?, ray + ? bone.] (Anat.) One of the bones at the base of a paired fin of a fish. [1913 Webster] … The Collaborative International Dictionary of English
actinost — one of a series of endochondral bones in the pectoral and pelvic girdle on which the fin rays insert. Most teleosts lack or have greatly reduced pelvic actinosts. Teleosts have one row of actinosts between the fin rays and supporting skeleton… … Dictionary of ichthyology
actinost — ac·ti·nost … English syllables
actinost — ˈaktəˌnäst noun ( s) Etymology: actin + ost : one of certain small bones directly supporting the rays of paired fins of teleost and some ganoid fishes called also carpal, pterygiophore; compare hypercoracoid … Useful english dictionary
brachial ossicle — actinost (one of a series of endochondral bones in the pectoral and pelvic girdle on which the fin rays insert. Most teleosts lack or have greatly reduced pelvic actinosts. Teleosts have one row of actinosts between the fin rays and supporting… … Dictionary of ichthyology
os actinostum — (plural ossa actinosta)) actinost (one of a series of endochondral bones in the pectoral and pelvic girdle on which the fin rays insert. Most teleosts lack or have greatly reduced pelvic actinosts. Teleosts have one row of actinosts between the… … Dictionary of ichthyology
-ost — ˌäst also ˌȯst noun combining form ( s) Etymology: Greek osteon : bone actinost … Useful english dictionary
pterygiophore — təˈrijēəˌfō(ə)r, teˈr noun ( s) Etymology: pteryg + phore : one of the cartilaginous or bony elements (as basalia and radialia) by which rays of the fin of a fish are supported : actinost … Useful english dictionary
pterygophore — təˈrigəˌfō(ə)r, ˈterəgōˌf noun ( s) Etymology: pteryg + phore : actinost … Useful english dictionary
pterygial — I. təˈrij(ē)əl, (ˈ)te|r adjective Etymology: New Latin pterygium + English al : of or relating to a pterygium II. noun ( s) : a pterygial bone or cartilage; specifically … Useful english dictionary
