The shape of the fungus is peculiar, a sort of semi-circular outline that may be called dimidiate.
"Among the Mushrooms" by Ellen M. Dallas and Caroline A. Burgin
We have accounts of dimidiate hermaphrodite lobster, male in one half and female in the other half of the body.
"The People's Common Sense Medical Adviser in Plain English" by R. V. Pierce
Harcourt, two bars, is dimidiated, and meets Beke, a cross moline or ancree.
"Notes and Queries, Number 191, June 25, 1853" by Various
Dimidiate -us: halved; extending half way around; applied to elytra when they cover only half the abdomen.
"Explanation of Terms Used in Entomology" by John. B. Smith
Dimidiation, accollation, and impalement succeeded each other at short intervals.
"Notes and Queries, Number 210, November 5, 1853" by Various
The correct blazon, I believe, would be: Or, an eagle double-headed, displayed sable, dimidiated, and impaling gu.
"Notes and Queries, Number 223, February 4, 1854" by Various
LA TOUCHE, J. D., on a Canadian apple with dimidiate fruit, i.
"The Variation of Animals and Plants Under Domestication, Volume II (of 2)" by Charles Darwin
The pileus is corky, dimidiate, sessile.
"The Mushroom, Edible and Otherwise" by M. E. Hard
P. tough, thin, unequal, excentric, dimidiate, cinnamon then pale, becoming squamulose, 3-9 cm.
"European Fungus Flora: Agaricaceae" by George Massee
And the chief standard of the people, which was the captain's, was dimidiated white and red.
"Villani's Chronicle" by Giovanni Villani
That this singular shield is a dimidiation of two antient coats cannot be doubted.
"The Curiosities of Heraldry" by Mark Antony Lower
Very slender, innovate-branching; leaves smaller, especially above, dimidiate-ovate or subfalcate, subdecurrent.
"The Manual of the Botany of the Northern United States" by Asa Gray
This "dimidiation," however, had its inconvenience.
"Encyclopaedia Britannica, 11th Edition, Volume 13, Slice 3" by Various