SYMMETRY IN TRAXSPLAXTED LIMBS 47 
(p. 49). The reduplicating limb is, of course, mirrored from the 
original and hence corresponds to the side of the body on ^Yhich 
it is grafted. 
Being placed in the position of the normal limb, the reduplica- 
tion is favorably situated with regard to blood and nerve supply, 
and it is probably on this account that so many of them develop 
into functional appendages. In this respect the experiments of 
this group differ considerably from the preceding (homopleural 
inverted), where there is a greater tendency for the original mem- 
ber to retain its predominant condition. Otherwise the course 
of development in the two groups is strikingly alike. 
For the study of the details of reduplication, nineteen cases 
are available, including one case with small wound not consid- 
ered in the table. Seven others were preserved at relatively 
early stages in order to investigate the internal processes involved. 
Histories of several typical cases are given in the appendix. 
Seventeen of the cases conform to the main type and do not 
differ materially from those considered in the last section. As in 
the homopleural inverted limbs (p. 35), the degree and character 
of the reduplication vary much from case to case. In some the 
digits alone are doubled, and at the other extreme we find two 
almost entirely separate limbs. In thirteen individuals a second 
reduplicating limb formed on the anterior side of the original. 
These usually did not develop so completely as the limbs arising 
from the posterior buds, and the reduplication often involved 
only the distal part of the manus, with the digits more or less sym- 
metrically placed. The anterior reduplications are mirrored 
from the ulnar or ulnopalmar surface and occasionally from the 
Figs. 67 to 70 Orthotopic transplantation; right limb to left side {het.dd.). 
Exp. R. E. 70. Resulting limb reduplicated. N, normal right limb bud; TR, 
transplanted limb bud; PR, primary member; DU, reduplicating member. X 10. 
Fig.67 Dorsal view, five days after operation. The transplanted bud already 
gives evidence of reduplication. 
Fig. 68 Dorsal view, ten days after operation. Redujjlicating bud is large 
and in normal position. 
Fig. 69 Dorsal view, sixteen days after operation. 
Fig. 70 Dorsal view of specimen preserved thirty days after operation. 
Fig. 71 Similar case (Exp. R. E. 71); ventral view, twenty-two days after 
operation. X 10. 
