• WordNet 3.6
    • n monotreme the most primitive mammals comprising the only extant members of the subclass Prototheria
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Webster's Revised Unabridged Dictionary
    • n Monotreme (Zoöl) One of the Monotremata.
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Century Dictionary and Cyclopedia
    • monotreme Same as monotrematous: as, monotreme mammals; a monotreme egg.
    • n monotreme A member of the Monotremata, as a duck-mole or prickly ant-eater.
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Chambers's Twentieth Century Dictionary
    • n Monotreme a member of the Monotremata
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Webster's Revised Unabridged Dictionary
Cf. F. monotrème,
Chambers's Twentieth Century Dictionary
Gr. monos, alone, trēma, a hole.


In literature:

We must, however, beware of simply transferring to the Mesozoic world the kinds of Monotremes and Marsupials which we know in nature to-day.
"The Story of Evolution" by Joseph McCabe
Australia as the only country inhabited by marsupials, monotremes and meliphagous birds.
"Darwin and Modern Science" by A.C. Seward and Others
Monotremes, birds compared with.
"More Letters of Charles Darwin Volume II" by Charles Darwin
Moreover, it requires a large amount of material to form a mammalian egg, such as that of the monotreme.
"The Whence and the Whither of Man" by John Mason Tyler
Monotremes, origin from birds, 342.
"Lamarck, the Founder of Evolution" by Alpheus Spring Packard
These are the Monotremes, represented by a very few species in Australia and New Guinea.
"The Chain of Life in Geological Time" by Sir J. William Dawson
In the Mammalia the eye is largely enclosed in the orbit, and bony plates in the sclerotic are only found in the monotremes.
"Encyclopaedia Britannica, 11th Edition, Volume 10, Slice 1" by Various
It is absent, for example, in the Monotremes.
"The Cambridge Natural History, Vol X., Mammalia" by Frank Evers Beddard
Still insane upon the subject of fossil monotremes, I suppose?
"Astounding Stories of Super-Science January 1930" by Victor Rousseau