Horse outward similarity is an unreliable measure of relatedness. Besides the horse, there are six other species of genus "Equus" in the Equidae family. These are the ass or donkey, "Equus asinus"; the mountain zebra, "Equus zebra"; plains zebra, "Equus quagga"; Grévy's zebra, "Equus grevyi"; the kiang, "Equus kiang"; and the onager, "Equus hemionus". Horses can crossbreed with other members of their genus. The most common hybrid is the mule, a cross between a "jack" (male donkey) and a mare. A related hybrid, a hinny, is a cross between a stallion and a jenny (female donkey). Other hybrids include the zorse,
The Adventures of a Donkey Gentleman's Magazine: and Historical Chronicle" said it was 'amusing and agreeable'. The only form of criticism is concerning Argus herself, a book review in the ninth volume of "The Literary Panorama 1806-1819" stated: 'We have repeatedly stated our opinion on the difficulty of writing books for children. Of that difficulty Mrs Argus has not been sufficiently sensible.' They go on to say that she cannot properly distinguish the difference between 'what is childlike and what is childish.' "The Critical Review, Or, The Annals of Literature" 1816 also stated that "The Adventures of a Donkey" lacks ability. The majority of criticism