A couple more photos might be useful, one showing a single glass and another the base clearly.
Assuming that they are from Murano, the 1920s or later would fit in terms of style, the fashion of the times turned to far simple wares. Out went the complexity and 'fussiness' that had been enjoyed by the Victorians for so long and in came simplicity and elegance, sophistication trumping bling to my eye!
John