i6 



FLORENCE PEEBLES. 



ficulty arose through e? cessive bleeding after the operation. This 

 usually esulted in the death of the embryo. 



A brief description of the behavior of one or two of the embryos 

 will suffice to show the general results. 



A. The leg and wing buds of an embryo, incub ted two days 

 in the shell and then two days in a porcelain cup, were removed. 

 The leg bud was grafted on the proximal part of the wing, and 

 the wing bud on the proximal pa, i of the leg. The embryo was 

 then placed in a moist chamber in the incubator where it was 

 left for three days. On removal it was found that the graft in 

 the wing region had separated, a d that the bud on the proximal 

 end of the leg was only partly attached (Fig. i, A). The left 

 side appeared as shown in Fig. i, B. There was no regeneration 

 in the wing region, and no apparent development in the leg 

 region. Sections of this embryo showed the normal limbs to be 

 composed of a homogeneous mass of mesoderm surrounded by 



FIG. 2. Two views of a chick on the eighth day. 

 grafts; B the normal side. 



A, the right side showing 



ectoderm. The limbs on the right side were similar in structure. 

 None of them showed distinguishing characteristics. 



B. The same experiment was performed on this embryo as on 

 the one just described. In this case the chick lived four days 

 after the grafts were made. Both unions were complete, as 



