S3 Method dispatch for ... or equivalent

Question

How do I define a method for a list of objects of the same class?

Eg.

foo <- letters[1:5]
foo2 <- letters[6:10]
class(foo) <- "abc"
class(foo2) <- "abc"
new_method <- function(...) {UseMethod("new_method", ...)}
new_method.abc <- function(...) {do.call("c", list(...))}

# use results in error
new_method(foo,foo2)
Error in new_method(foo, foo2) : '...' used in an incorrect context

Here I want ... to be an arbitrary length list of objects all of which have the same class and I want to do something with them (combine them, specific to my real class's use case).

It makes sense to me that ... doesn't have a class that can be sent to method dispatch; but a simple re-write also doesn't work since new_method.list doesn't / shouldn't exist

new_method <- function(...) {UseMethod("new_method", list(...))}
new_method(foo,foo2)
Error in UseMethod("new_method", list(...)) : 
  no applicable method for 'new_method' applied to an object of class "list"