Old-style Siamese Cats

An Old-style Siamese is not just a poor-quality (or 'pet-quality') show Siamese. Old-style Siamese meet the standard of points for the Siamese, without the extreme look of some show Siamese.
Applehead SiameseThere have never been appleheads in Britain-the applehead is something invented in America, often by outcrossing to other breeds such as the British Shorthair. This shortens the head and in many cases has gone as far from the original imported Siamese as the modern show cat, just in the opposite direction. None of the earliest pictures of the Siamese show appleheads, though the cats were cobbier than today's cats. A very few early pictures of Siamese from the late 1800s show a round-headed cat, but actually this is simply a male cat with a narrower head who has developed heavy jowls-some old-style studs look like this. These very cobby cats were also not Siamese as we know them: they were hybrids corresponding genetically to the modern-day Tonkinese.

FUENTE: http://www.marajade.co.uk/Siamese.htm