[tacticalogic]

IM NOT CERTAIN that they meant to say that nuclei were discovered within the Blood Cells as protein cells were also under the microscope

The only cells mentioned are the red blood cells. I don't see any mention of "protein cells", nor do I recall ever seeing that term in the chapters on the various cell types (but that was some considerable number of years ago).

[Boogieman]

“I don’t see any mention of “protein cells”, nor do I recall ever seeing that term in the chapters on the various cell types”

Correct, proteins are not cells, so there is no such thing as “protein cells”.