Batman (Volume 1 1940) Issues 301-350
Key Issues include;
#307 - 1st appearance of Lucius Fox
#308 - 1st appearance of Tiffany Fox, daughter of Lucius Fox (later Batgirl)
#313 - Batman and Catwoman first date and kiss, 1st appearance of Tim Fox, son of Lucius Fox
#318 - 1st appearance of Firebug
#326 - 1st mention of Arkham Asylum
#331 - 1st appearance (death) of the Electrocutioner
#332 - 1st Catwman solo story
#345 - 1st appearance of Dr Death in Bronze Age