Error putting horizontal series of cells into array .....why?

I have the folllowing code which is supposed to put cells B2 through B25 into an array.

month_array1 = ws.Range(Cells(2, 13), Cells(2, 25)).Value

But it does not work............what does work is the following:

month_array2 = ws.Range("B2:B25").Value

but i dont know why the 2nd worked but the first did not? anyone have any ideas?