Mark Taylor / Black and white Jack-a-poo, Jack Russell cross Poodle, pup, 8 weeks old, jumping up.

Florian Möllers / 'Jogi', a Jack Russell Terrier cross breed, male playing in the snow. Germany

Jane Burton / Two smooth coated Jack Russell Terrier puppies, tan and white, 6 weeks,

Mark Taylor / Smooth coated Jack Russell Terrier puppy, black and white, 9 weeks, sitting, looking up

Jane Burton / Two Rough coated Jack Russell Terrier puppies playing with boot lace

Jane Burton / Rough coated Jack Russell Terrier puppy, black and tan, portrait

Jane Burton / Rough coated Jack Russell Terrier puppy, black, tan and white, portrait

Jane Burton / Rough coated Jack Russell Terrier puppy, tan and white, with a boot

Jane Burton / Smooth coated Jack Russell Terrier, black, tan and white, female with two 8 week puppies

Mark Taylor / Rough coated Jack Russell Terrier, tan and white, lying down, panting

Jane Burton / Smooth coated Jack Russell Terrier, white, looking up, standing on back legs

Ernie Janes / Jack russell terrier in box with Christmas tree