Hircocervus

In Plato's Republic, Socrates speaks of his own image-making as similar to that of painters who paint goat-stags, combining the features of different things together (488a).

[1] In his work De Interpretatione,[2] Aristotle utilized the idea of a fabulous goat-stag to express the philosophical concept of something that is describable even though it does not really exist.

On the other hand, Diodorus Siculus treats the tragelaphos as an existing animal, and there are references in Greek literature to other hybrid creatures such as the hippelaphos (horse-stag).

[3] Rabbinic literature refers to an animal called a koy which is halfway between domesticated and wild species of quadruped, and debates how far it is subject to the laws governing each category.

The dual party of socialists and capitalists "thus becomes a hircocervus, a historical monster devoid of will or particular aims, concerned only with its possession of the state.

This is a woodcut is of the tragelaph from the book, The History of Four-footed Beasts and Serpents by Edward Topsell .
Hircocervus from Naturalis Historiae by Pliny the Elder .
19th century engraved reproduction of "The Trusty Servant"