The Wire and Smooth Fox Terriers share similar characteristics, the main differences being in the coat and markings.

[1] The earliest record of any white terrier was a dog named Pitch, who was owned by Colonel Thomas Thornton in 1790.

"[2] Dog writers of the early 20th century suggested that Pitch was a terrier-greyhound cross, which was how the colour was introduced into the breed.

Old Jock was bred from a black and tan terrier, while Trap was from the strain out of Reverend John "Jack" Russell's dogs.

[6] In addition to those dogs, another named Old Tip is thought to be the forefather of the modern Wire Fox Terrier.

The terrier of this period was short of leg, built in a chunky fashion, and had a skull that was broad across the top.

Used in hunting packs and kept in kennels along with English Foxhounds, they were bred for their ability to drive the fox out of its den.

[7] Gradually the pace of the hunt became faster, and the terriers were bred with longer legs for more speed towards the end of the 18th century.

[10] Both major types of Fox Terrier are mostly white with coloured markings and have similar facial characteristics.

The head of this breed is long and wedge shaped, with small, dark eyes and ears that are v-shaped.

[21] The Wire Haired Fox Terrier has a hard and crisp double coat with a coarse texture underneath that provides protection from the cold.

[15] An average member of the breed should measure 14–15.5 inches (36–39 cm) at the withers and weigh 15–19 pounds (6.8–8.6 kg).

It has similar features to the Smooth Fox Terrier, with small dark eyes and v-shaped ears.

[24] Myasthenia gravis, a neuromuscular disease, is hereditary in the Smooth Fox Terrier through an autosomal recessive gene.