1773, from Modern Latin (Linnaeus), from neuter plural of Late Latin mammalis, from mamma (see mammal).
Examples from the Web for mammalia
In Aves and Mammalia (fig. 355) they are mainly confined to the dorsal and lateral parts.The Works of Francis Maitland Balfour, Volume III (of 4)|Francis Maitland Balfour
We have heretofore mentioned the possibility of the appearance of the mammalia before the bird.
I have already mentioned nearly all the mammalia common in this country.A Naturalist's Voyage Round the World|Charles Darwin
Maule appealed to the court: 'My lords, we are vertebrate animals, we are mammalia!Familiar Quotations|John Bartlett
More extended observations on Mammalia will perhaps shew that even this difference does not hold good.The Works of Francis Maitland Balfour, Volume 1|Francis Maitland Balfour