Gallon pints. These pints are divided into two cups (though the imperial cup is rarely used now), which in turn are divided into two gills (gills are also rarely used). Thus a gallon is equal to four quarts, eight pints, sixteen cups or thirty-two gills. The imperial gill is further divided into five fluid ounces, whereas the US gill is divided into four fluid ounces. Thus an imperial fluid ounce is of an imperial pint or of an imperial gallon, while a US fluid ounce is of a US pint or of a US gallon. The imperial gallon, quart, pint, cup
External gills External gills External gills are the gills of an animal, most typically an amphibian, that are exposed to the environment, rather than set inside the pharynx and covered by gill slits, as they are in most fishes. Instead, the respiratory organs are set on a frill of stalks protruding from the sides of an animals head. This type of gill is most commonly observed on the aquatic larva of most species of salamanders, lungfish, and bichirs (which have only one large pair), and are retained by neotenic adult salamanders and some species of adult lungfish. They are present on non-transforming