r - 行数が異なるリストのメンバーをマージするには

Question

コンソールで実行できるリストは次のとおりです (例として長すぎる場合は教えてください。修正できます)。

my_list = list(structure(list(PX_LAST = c(0.398, 0.457, 0.4, 0.159, 0.126, 
0.108, 0.26, 0.239, 0.222, 0.191, 0.184)), .Names = "PX_LAST", row.names = c("2014-04-28 00:00:00", 
"2014-04-29 00:00:00", "2014-04-30 00:00:00", "2014-05-02 00:00:00", 
"2014-05-05 00:00:00", "2014-05-06 00:00:00", "2014-05-07 00:00:00", 
"2014-05-08 00:00:00", "2014-05-09 00:00:00", "2014-05-12 00:00:00", 
"2014-05-13 00:00:00"), class = "data.frame"), structure(list(
    PX_LAST = c(1.731, 1.706, 1.7095, 1.69, 1.713, 1.711, 1.724, 
    1.699, 1.702, 1.705, 1.649, 1.611)), .Names = "PX_LAST", row.names = c("2014-04-29 00:00:00", 
"2014-04-30 00:00:00", "2014-05-01 00:00:00", "2014-05-02 00:00:00", 
"2014-05-05 00:00:00", "2014-05-06 00:00:00", "2014-05-07 00:00:00", 
"2014-05-08 00:00:00", "2014-05-09 00:00:00", "2014-05-12 00:00:00", 
"2014-05-13 00:00:00", "2014-05-14 00:00:00"), class = "data.frame"), 
    structure(list(PX_LAST = c(0.481, 0.456, 0.448, 0.439, 0.436, 
    0.448, 0.458, 0.466, 0.432, 0.437, 0.441, 0.417, 0.4035)), .Names = "PX_LAST", row.names = c("2014-04-28 00:00:00", 
    "2014-04-29 00:00:00", "2014-04-30 00:00:00", "2014-05-01 00:00:00", 
    "2014-05-02 00:00:00", "2014-05-05 00:00:00", "2014-05-06 00:00:00", 
    "2014-05-07 00:00:00", "2014-05-08 00:00:00", "2014-05-09 00:00:00", 
    "2014-05-12 00:00:00", "2014-05-13 00:00:00", "2014-05-14 00:00:00"
    ), class = "data.frame"), structure(list(PX_LAST = c(1.65, 
    1.65, 1.64, 1.65, 1.662, 1.6595, 1.665, 1.6595, 1.6625, 1.652, 
    1.645, 1.6245, 1.627, 1.633)), .Names = "PX_LAST", row.names = c("2014-04-25 00:00:00", 
    "2014-04-28 00:00:00", "2014-04-29 00:00:00", "2014-04-30 00:00:00", 
    "2014-05-01 00:00:00", "2014-05-02 00:00:00", "2014-05-05 00:00:00", 
    "2014-05-06 00:00:00", "2014-05-07 00:00:00", "2014-05-08 00:00:00", 
    "2014-05-09 00:00:00", "2014-05-12 00:00:00", "2014-05-13 00:00:00", 
    "2014-05-14 00:00:00"), class = "data.frame"))

私の質問はdo.call()、そのリストを使用して、日付に従ってすべてのデータをマージするにはどうすればよいですか?

どちらかを検討して、私が管理できないエラーを返しますmerge。cbind

> do.call(what = merge, args = my_list)
Error in fix.by(by.x, x) : 
'by' must specify column(s) as numbers, names or logical

> do.call(what = cbind, args = my_list)
Error in data.frame(..., check.names = FALSE) : 
arguments imply differing number of rows: 11, 12, 13, 14

の要素でNA使用するものと等しい単一のデータ行列 (欠落している/一致しないデータが s に置き換えられる可能性があります) を取得したいと思います。merge()my_list