GENERAL APPEARANCE
Shoulder height: Jack Russell 25-30cm (10”-12”).
Parson Jack Russell 30-35cm (12”-14”).
Colour: White predominates. Black, tan or brown markings often on head, ears and/or root of their tail.
Coat: Three types - rough, smooth or broken. Gait: Free, sound - fore and hindlegs moving straight.
These working terriers should be bold and confident at all times. The skull should be flat and moderately broad with a muzzle shorter than the skull.
The dark eyes are almond shaped and the small ears are set high with the tips dropping forward. The strong neck runs into long sloping shoulders and a straight back. The powerful hindlegs are well bent at the stifles and finish with round feet. The high set tail signifies alertness but may drop at rest.
CHARACTERISTICS AND CARE
Brash, energetic and enterprising are characteristics which signify the hall marks of these popular dogs. In addition to speed and stamina, these game little terriers were expected to mix compatibly with -all dogs, farm stock and people and to behave well in the house. Coat care is minimal in the Smooth coated variety and only periodic brushing or tidying up to keep the Broken or Rough varieties in good condition.
HISTORY 
In 1812, the irascible Parson Jack Russell purchased a terrier named Trump who ultimately became the foundation of the strain that took his owner’s name. Being interested in hunting, Russell soon collected a scratch pack to hunt foxes and hares which, after a few years of judicious breeding and selection, were able to acquit themselves extremely well in the field. Their reputation and their popularity grew. Russell preferred his terriers to be at least 5lcm (20”) tall. However, while still retaining their character, the shorter (and often crooked) legged variety with heavier bodies were also being bred.
By the early part of the 20th century, many breeders were endeavouring to get more conformity in breed type in order to gain official recognition so the breed could be exhibited at championship shows.