• Webster's Revised Unabridged Dictionary
    • n Balanoglossus (Zoöl) A peculiar marine worm. See Enteropneusta, and Tornaria.
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Century Dictionary and Cyclopedia
    • n balanoglossus An extraordinary genus of invertebrate animals, the type not only of a family, Balanoglossidæ, but also of an order or even a distinct class of animals, Enteropneusta (which see). It is related in its mode of development to the echinoderms, in some respects to the ascidians, and is usually classed with the Vermes. The members of this genus are elongated, footless, soft-bodied worms, with the mouth at one end of the body and the anus at the other. The fore part of the body presents a kind of collar surrounding a constriction from which springs a long hollow proboscis-like organ, whence the name Balanoglossus, this organ being like a tongue somewhat acorn-shaped, proceeding from within the collar like an acorn from its cup. On the portion of the body from which the proboscis springs there is a flattened area with a longitudinal series of branchial apertures, communicating with branchial sacs connected with the alimentary canal; hence the term Enteropneusta. In consequence of this relation of the respiratory to the alimentary canal, Huxley associates Balanoglossus with Tunicata (or ascidians) as members of a pharyngopneustal series. The larval form of Balanoglossus was formerly called Tornaria, and regarded as an echinoderm from its great resemblance to the larva of a starfish.
    • n balanoglossus [lowercase] A member of the genus Balanoglossus.
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Webster's Revised Unabridged Dictionary
NL., fr. Gr. ba`lanos acorn + glw^ssa tongue


In literature:

Balanoglossus is one of them, the Acorn-tongue Animal.
"Stories of the Universe: Animal Life" by B. Lindsay