Proc. Roy. Socy. of Edin.] 
[ Vol. XXYII. 
Fig. 1 .— The Marrow of a Rat set. three weeks, unweaned. 
Mother fed on a bread-and-milk diet. ( x 200. ) 
Note the leucoblastic type of marrow, the white blood corpuscles 
being in excess of the red blood corpuscles. Cf.. fig. 2. 
Fig. 2. —The Marrow of a Rat set. three weeks, unweaned. 
Mother fed on an ox-flesh diet. ( x 200.) 
Note the erythroblastic type of marrow, the red blood corpuscles 
being more numerous than the leucocytes. Cf. fig. 1. 
Dr Chalmers Watson. 
[Piate I. 
