NEUTRON EFFECTS OX ANIMALS 99 



methods. The bone marrow extracts, all of which were pigmented with 

 hemoglobin, were photographed with three different exposures to insure 

 clear pictures of all parts of the electrophoresis patterns. Area measure- 

 ments were made on enlarged tracings of the Svensson diagrams. The 

 protein concentrations computed from these areas, reported in Tables III, 

 I\", \, and \T for the plasmas and sera, and in Table "\TI for the bone 

 marrow extracts, are all expressed as refractive increments, since the exact 

 specific refractive increments recjuired to convert these values to grams per 

 100 ml. are not known. Each value represents the average from four 

 different diagrams. 



Electrophoretic analyses were made of plasma and serum from each 

 blood sample in the expectation that the difference between the two 

 analyses would yield the fibrinogen content with greater precision than is 

 possible from analysis of the plasma alone. It was found, however, that 

 the total protein content was as a rule greater for the serum than for the 

 plasma, in spite of the absence from the serum of the clot -forming elements. 

 Nevertheless, it was possible to superpose the plasma and serum patterns, 

 as sho^\Tl in the diagTams at the top of Fig. 2, and from the area between to 

 determine the fibrinogen content with less error than from the plasma 

 pattern alone. It can be seen from this diagram that part of the area which 

 is assigned to fibrinogen by the usual method of dropping ordinates from 

 the minima on either side of the fibrinogen peak belongs instead to the 7 

 globulin. 



Of the four animals initially selected for these experiments, three. A, C, 

 and D, gave consistent plasma and serum analyses, as shown in Table III. 

 The fourth, B, showed higher concentrations of jS globulin and fibrinogen; 

 and E, a fifth rabbit acquired later, showed a higher concentration of 7 

 globulin. Rabbits A and C were therefore selected for neutron irradiation, 

 and rabbits B, D, and E served as controls without irradiation. 



Plasma and Serum Com'posiiion of Successive Blood Samples from Non- 

 Irradiated Rabbits. Two of the three non-irradiated rabbits were under 

 observation for several weeks. One of the two, rabbit D, which on the 

 first day of observation closely resembled rabbits A and C with respect 

 to plasma composition, showed very little variation in plasma composition 

 throughout the period of observation. There was no significant change 

 on the twelfth day, and only a slight rise in /3 globulin on the 56th day 

 (Table IV). The other, rabbit B, which on the first day of observation 

 had a higher content of /3 globulin and fibrinogen than A, C, and D, showed 

 fairly wide fluctuations. On the 56th day the a and /3 globulin concen- 

 trations were diminished, and the 7 globulin concentration was almost 

 doubled. On the 110th day the plasma showed almost complete restora- 

 tion of the a and /3 globulins, a small increase in fibrinogen with respect to 



