Which preposition to use with crania

from Occurrences 5%

The few crania from there which have been intrusted to me bear the marks of recent pedigree, as also do the additional objects.

in Occurrences 1%

Up to that time next to nothing was known of deformed crania in the oriental island world.

under Occurrences 1%

It rested on its apex (base uppermost), and was filled with fragments of half incinerated human bones, mingled with dark-colored dust, and the sand which invariably sifts into crania under such circumstances.

Which preposition to use with  crania