“…The change was not, however, consistent in its direction, the contractions being sometimes more, sometimes less frequent. The failure to find a constant effect of morphine on the frequency of contractions is in agreement with the results of Gruber, Brundage, DeNote, and Heiligman (1935) in dogs, and of Abbott and Pendergrass (1936) in man, but an increased frequency after morphine has been reported by Forster (1940), Devine (1946), andPlant andMiller (1926), and a decrease in frequency has been said to occur after morphine by Krueger, Howes, andGay (1935) andby Oettel (1935).…”