=Hurried breathing= occurring independently of exercise, heat of the atmosphere, or distension of the abdomen, is indicative of fever, especially if associated with rapid pulse and increased heat of the body. Infrequent respiration appears in certain brain diseases in the intervals between the more violent paroxysms, also in poisoning by opium and other narcotics. =Tardy or slow respirations= differ from those last noticed in the act occupying a longer time. In infrequent breathing the act may be short, though there are few respirations in the minute. This is likewise seen in brain diseases and sometimes in broken wind. In the last case there is =double action of the flank=, each act of expiration being effected by two successive and distinct elevations of the flank. =Quick breathing= in which the act occupies only a short time is usually abruptly cut off, the inspiration terminating by a catch or jerk. It is significant of the early stage of pleurisy, and arises from the desire to avoid the pain attendant on the rubbing together of the inflamed surfaces during deep inspirations. It is further seen in tetanus, peritonitis, pericarditis and pleurodynia. =Deep breathing= with great lifting of the flanks and loins is characteristic of water in the chest, and consequent inability to inflate the lungs. =Labored breathing=, which is at once hurried, deep, and without intermission, is seen in severe laryngitis, croup, capillary bronchitis, and pneumonia, in all cases alike from the difficulty experienced in introducing into the lungs the requisite amount of air. It is especially marked in double pneumonia, pleuro-pneumonia, complicated with effusion in the chest, and in old standing _broken wind_ with dilatation of the right heart. In all such cases where there is much interference with the æration of blood, whether from obstruction to the circulation of blood or a hindrance to the introduction of air, the horse invariably stands. The fact that he has lain down may be taken as an indication that improvement has taken place. The peculiarity is due to the sharp outline of the horse’s sternum inferiorly so that in lying down he is compelled to rest on his side and the whole weight of the body tends to compress the chest. In the ox, sheep, pig and dog, which can rest on the sternum, breathing can be carried on with comparative ease in the recumbent position, and these animals accordingly do not necessarily stand except in very extensive and violent affections of the chest. The occurrence of a short inspiration suddenly checked and a prolonged expiration characterizes pleurisy, the check to the inspiratory act being because of the pain caused by dilating the thorax.