Eureka wrote:Is this just [face=SPIonic]e)n[/face] +dative with the [face=SPIonic]e)n[/face] left off?
Or, is the meaning in any way different from [face=SPIonic]e)n[/face] +dative?
The meaning will often be the same, but the dative should be considered on its own. The IE locative case merged with the dative in Greek, and this poetic usage is the last vestage of it (along with things like [face=spionic]oi)/koi[/face]
). It merely indicates a fixed location; a preposition refines that meaning.
Smyth 1531 has various examples, too.