Named components in a list

I'm studying lists and I came to an example where

L

$name
[1] "Fred"

$wife
[1] "Mary"

$no.children
[1] 4

$child.ages
[1] 4 7 9

then following the instructions to extend the list with a new component, I 
executed:

L[5] <-list(NewName="something")

and the new list I got was:

L

$name
[1] "Fred"

$wife
[1] "Mary"

$no.children
[1] 4

$child.ages
[1] 4 7 9

[[5]]
[1] "something"

Here the 5th element lacks the name "NewName" ... maybe this is a bug. Do you 
have any comments?

Thanks,

Sergio.