I think only people who are especially strong dog fanciers would think of
Jack Russell terriers as their first association to this name.
The previous quote about
Russell sounding "terribly posh" is humorous to me personally because
Russell was the name of my late favorite uncle.
He was anything but "posh", but was a great blue-collar guy who loved horses and Western wear.
He was a good old country boy at heart who loved kids and animals. When he died at age 90, his family had his casket moved from the church to the cemetery in a horse drawn wagon. :)