SYMMETRY IN TRANSPLANTED LIMBS 75 
three cases the other prominence persisted also, at the elbow in 
one"^ in the form of a spur (fig. 124), and as a nodule at the 
shoulder in two others.^" In the remaining case*^ all external 
traces of reduplication disappeared. 
On the other hand, two of the cases of reduplication are of an 
anomalous nature and cannot be regarded as conforming to the 
rule. Both of these were experiments in which the anterior half 
of the limb bud was replaced by a posterior half. We should 
expect in such a case to find posteriorly a homopleural member 
developed out of the stationary portion of the bud, while anteri- 
orly there should be a reversed limb which might itself be redu- 
plicated. The opposite is, however, true. In both cases the an- 
terior member is not reversed. The posterior member is reversed 
(a left) in one case^- (fig. 126) and in the other ^^ it is itself double, 
the anterior portion being reversed and the posterior homopleural 
(fig. 125). 
The operated limb in all of these cases was composed of two 
homogeneous halves. 
Histories of typical cases are given in the appendix (p. 132). 
20. Heteropleural transplantations, dorsodorsal orientation. 
This combination, being disharmonic, yielded out of seventeen 
cases twelve duplicities (figs. 127 and 129) and three limbs that 
became normal by reduction of the reduplicating member (fig. 
130). In two individuals^^ normal limbs resulted without exter- 
nal evidence of incipient doubling, and two of the reduplications, 
in one of which both members are of the same side in linear series, 
are of an anomalous nature. This makes foUr cases out of sev- 
enteen that do not follow the rule. Two of the combinations 
are heterogeneous; all of these conform to the rule except one of 
the anomalous reduplications. The other three non-conforming 
cases belong in the homogeneous class, and it is interesting that 
all of the normal cases in this group resulted from the combina- 
tion of two like halves. 
'3 H. E. 2. 82 H. E. 13. 
8" H. E. 18 and 21. s^ h. E. 5. 
81 H. E. 4. 84 H. R. E. 43 and 44. 
