Studies on the Chemical Composition of Beef Blood. I. the Concentrations of Certain Constituents in Nor-

For many years beef blood has served as the medium for abstract experimentation on blood. The methods of analysis which have been so highly developed during t,he past 10 years have been largely worked out on the blood from slaughtered cattle. Much of our fundamental knowledge of blood chemistry has been acquired from the same source. But recently in undertaking the study of the effect of certain restricted rations on such animals it was discovered that the data on the chemical composition of normal beef blood available for application to a study of the physiological processes of dairy cows were extremely meager. The studies hitherto pursued had dealt with beef blood merely as blood and had served only as a means to an end, the end being considerations other than the animals furnishing the blood. Among the few who have secured information on the subject, Abderhalden (1) was among the first. He analyzed the bloods from several domestic animals, among them two beeves. Hart (2, 3, 4) and his collaborators have recorded a few determinations on calcium and phosphorus in blood and the changes in the concentrations of these two constituents under the influence of various factors affecting calcium assimilation. Meigs, Blatherwick, and Gary (5) have studied the calcium and phosphorus