Question: Does the Landseer or English Mastiff have a limited range of colors? 

full_context: Document 1: Mastiff: Mastiff type means a large molosser dog. The term "mastiff type" has been used synonymously with the term "molosser". For example, the bulldog breeds, the Great Dane, the mountain dogs, the pit bulls and even smaller dogs such as the Boston terrier, may be considered "mastiff types" in this broad sense. The descriptive term, mastiff type, should not be confused with the breed, the Mastiff. All breeds are individual and should be referred to by their breed name to ensure correct identification.
Document 2: Neapolitan Mastiff: The Neapolitan Mastiff or Mastino (Italian: "Mastino Napoletano" ) is a large, ancient dog breed. This massive breed is often used as a guard and defender of family and property due to their protective instincts and their fearsome appearance.
Document 3: Great Dane: The Great Dane is a large German breed of domestic dog known for its giant size. The German name of the breed is "Deutsche Dogge", or German Mastiff. The French name is "Dogue Allemand."
Document 4: Seskar Seal Dog: The Seskar Seal Dog ("Seiskarinhyljekoira") is an extinct dog breed from Finland that was recently recreated. The modern dogs are not direct descendants of the original breed. Moreover, they are not used for the same purpose as the original breed. The original breed is typically called Seskar Seal Dog and the modern version Seskar (or Seiskari) Dog. Some 200 individuals in Finland represent the modern breed.
Document 5: Dogue de Bordeaux: The Dogue de Bordeaux, Bordeaux Mastiff, French Mastiff or Bordeauxdog is a large French Mastiff breed—and one of the most ancient French dog breeds. A typical brachycephalic molossoid type breed, the Bordeaux is a very powerful dog, with a very muscular body. This brawny breed has been put to work in many different capacities, from pulling carts and hauling heavy objects, to guarding flocks and, historically, the castles of the European elite.
Document 6: Welsh Springer Spaniel: The Welsh Springer Spaniel is a breed of dog and a member of the spaniel family. Thought to be comparable to the old Land Spaniel, they are similar to the English Springer Spaniel and historically have been referred to as both the Welsh Spaniel and the Welsh Cocker Spaniel. They were relatively unknown until a succession of victories in dog trials by the breed increased its popularity. Following recognition by The Kennel Club in 1902, the breed gained the modern name of Welsh Springer Spaniel. The breed's coat only comes in a single colour combination of white with red markings, usually in a piebald pattern. Loyal and affectionate, they can become very attached to family members and are wary of strangers. Health conditions are limited to those common among many breeds of dog, although they are affected more than average by hip dysplasia and some eye conditions. They are a working dog, bred for hunting, and while not as rare as some varieties of spaniel, they are rarer than the more widely known English Springer Spaniel with which they are sometimes confused.
Document 7: Landseer (dog): The "'Landseer" is a dog breed. The breed is not recognized by all kennel clubs . It is not to be confused with a white and black Newfoundland, which is also often called a "landseer".
Document 8: St. John's water dog: The St. John's water dog, also known as the St. John’s dog or the lesser Newfoundland, was a landrace (a dog bred for a purpose, not pedigree or appearance) of domestic dog from Newfoundland. Little is known of the types that went into its genetic makeup, although it was probably a random-bred mix of old English, Irish and Portuguese working dogs. The number of St. John's water dogs started declining by the start of the 20th century. By the early 1980s, the variety was extinct.
Document 9: Shetland Sheepdog: The Shetland Sheepdog, also known as the Sheltie, is a breed of herding dog. The original name of this breed was Shetland Collie, but this caused controversy among the Rough Collie breeders at the time, so the breed's name was formally changed to Shetland Sheepdog. This small dog is intelligent, vocal, excitable, energetic and willing to please and work hard. The breed was formally recognized by The Kennel Club in 1909.
Document 10: Bullmastiff: The Bullmastiff is a large-sized breed of domestic dog, with a solid build and a short muzzle. The Bullmastiff shares the characteristics of molosser dogs, and was originally developed by 19th-century gamekeepers to guard estates. The breed's bloodlines are drawn from the English Mastiff and the extinct Old English Bulldog. It was recognized as a purebred dog by the English Kennel Club in 1924. They are quiet dogs and very rarely bark.
Document 11: Alpine Mastiff: The Alpine Mastiff is an extinct Molosser dog breed, the progenitor of the St. Bernard, and a major contributor to the modern Mastiff (through such dogs as "Couchez"), as well as to other breeds that derive from these breeds or are closely related to them. M.B. Wynn wrote, "In 1829 a vast light brindle dog of the old Alpine mastiff breed, named L'Ami, was brought from the convent of Great St. Bernard, and exhibited in London and Liverpool as the largest dog in England." William Cavendish, 5th Duke of Devonshire, is believed to have bred Alpine Mastiffs at Chatsworth House.
Document 12: Newfoundland (dog): The Newfoundland dog is a large working dog. They can be either black, brown, or white-and-black (called Landseer). However, in Canada, the country of their origin, the only correct colours are either black or Landseer. They were originally bred and used as a working dog for fishermen in the Dominion of Newfoundland (which is now part of Canada). They are known for their giant size, intelligence, tremendous strength, calm dispositions, and loyalty. Newfoundland dogs excel at water rescue/lifesaving because of their muscular build, thick double coat, webbed feet, and innate swimming abilities.
Document 13: Molossus of Epirus: The Molossus of Epirus (Greek: Μολοσσός της Ηπείρου) is a large dog breed originating from Greece. It is a livestock guardian that has been bred since the age of Alexander the Great for protecting livestock from carnivorous mammals including the wolf, European jackal and the brown bear in the mountainous regions of Greece, especially Epirus. The Molossus is a pure Greek breed and is believed to be one of the main ancestors of today's Molosser breeds, such as the English Mastiff and the Neapolitan Mastiff,
Document 14: Lakeland Terrier: The Lakeland Terrier is a dog breed, which takes its name from its place of origin, the Lake District in England. The dog is a small to mid-size member of the Terrier family. While independent in personality, it interacts well with owners and all family members, and is mostly hypo-allergenic (non shedding). The breed is not widely owned in the United States.
Document 15: English Mastiff: The English Mastiff is a breed of extremely large dog (often known simply as the Mastiff) perhaps descended from the ancient Alaunt and Pugnaces Britanniae, with a significant input from the Alpine Mastiff in the 19th century. Distinguishable by enormous size, massive head, and a limited range of colours, but always displaying a black mask, the Mastiff is noted for its gentle and loving nature. The lineage of modern dogs can be traced back to the early 19th century, but the modern type was stabilised in the 1880s and refined since. Following a period of sharp decline, the Mastiff has increased its worldwide popularity. Throughout its history, the Mastiff has contributed to the development of a number of dog breeds, some generally known as Mastiff-type dogs, or, confusingly, just as "Mastiffs".
ground_truth: English Mastiff