(Lat. quatuor, four; manus, hand). The order of Mammals comprising the Apes, Monkeys, Baboons, Lemurs, etc.
(Lat. radius, a ray). A division of Protozoa.
(Lat. a spoke or ray). The innermost of the two bones of the forearm of the higher Vertebrates. It carries the thumb, when present, and corresponds with the tibia of the hind-limb.
(Lat. a branch). Applied to each half or branch of the lower jaw or mandible of Vertebrates.
(Lat. rapto, I plunder). The order of the Birds of Prey.
(Lat. rado, I scratch). The order of the Scratching Birds (Fowls, Pigeons, &c).
(Lat. rates, a raft). Applied by Huxley to the Cursorial Birds, which do not fly, and have therefore a raft-like sternum without any median keel.
(Lat. rectus, straight). The terminal portion of the intestinal canal, opening at the surface of the body at the anus.
(Lat. repto, I crawl). The class of the Vertebrata comprising the Tortoises, Snakes, Lizards, Crocodiles, etc.
(Lat. a net). The second division of the complex stomach of Ruminants, often called the "honeycomb-bag."
(Gr. rhiza, root; phago, I eat). A group of the Marsupials.
(Gr. rhiza, a root; and pous, foot). The division of Protozoa comprising all those which are capable of emitting pseudopodia.
(Gr. rhunchos, beak ; and lithos, stone). Beak-shaped fossils, consisting of the mandibles of Cephalopoda.
(Lat. rodo, I gnaw). An order of the Mammals ; often called Glires (Lat. glis, a dormouse).
(Lat. rostrum, beak). The "beak" or suctorial organ formed by the appendages of the mouth in certain insects.