Just saying. John J. McKay at his blog Archy used Google Books in 2009 to ferret out Lyell as the original source of a succession of uncited reproductions.
Why do I find this interesting? On the one hand, it is quite clear that at least on of the persons involved simply copied the words of a source verbatim without marking it as a quote, though he does mention his source in a footnote. On the other hand, the passage in question and its replications are clearly only reporting about the discovery by M. Middendorf of a mammoth in excellent condition. None of the reporters, including Lyell's, claims the discovery to be his own. That is, all reporters, including the parrots, respect the priority of Middendorf.
According to our standards, this would probably be plagiarism, because copying the words of a source without marking it as a quote is probably enough, even if a footnote refers to the source. Nevertheless, it is not a theft of a discovery or an invention.
According to past standards this sort of parroting was probably borne with nonchalance signifying only that the parrot was not able to improve on the language of his source. This parroting of sensational findings also occurs today in what is called science journalism (though journalists usually mark their quotes properly). Anyway, I disagree with Archie on the interpretation of this case. Words were copied, but no idea or discovery or invention stolen. I do not think the Victorians cared.