SYMMETRY IN TRANSPLANTED LIMBS 109 
of the bud, but the priinai-y bud also gains a headway m develop- 
ment that usualh' cannot be overcome even by the more advan- 
tageous position of the reduplicating bud. In the heterotopic 
operations the frequency of reduplication in the harmonic group 
may be ascribed to the disturbance due to the operation, together 
with lack of any special anatomical relations at the seat of implan- 
tation that would overcome the tendency to bud by giving the 
harmonic member a special advantage. All that remains to be 
accounted for is, therefore, the small proportion of reduplica- 
tions in the disharmonic group. This should be subjected to 
further investigation. Standing alone, it can hardly be advanced 
as an argument for a teleological theory of development. 
GENERAL SUMMARY 
1 . The results given below are based upon the following experi- 
ments with the fore-lunb bud of the embryo of Amblystoma 
punctatimi : 
a. Transplantation to the flank of another embryo posterior 
to the normal position of the fore luxib (heterotopic transplanta- 
tion), the grafted buds being taken either from the same side of 
the body (homopleural) or from the opposite ( heteropleural) , and 
miplanted with the dorsoventral axis upright (dorsodorsal) or 
inverted (dorsoventral) . 
h. Transplantation to the normal location of the fore Imib 
after extirpation of the original fore-limb rudiment (orthotopic 
transplantation), with the same variations as in the heterotopic 
group. 
c. Superposition of one lunb bud upon another after removal of 
the ectodermal covering of the latter, also with the same varia- 
tions as in the previous groups. 
d. Transplantation of half of the circular disc constituting the 
limb bud, after extirpation of one-half the rudiment. Sixteen 
different combinations of this 'experiment fall possible within the 
limitations imposed) were tried fp. 70). 
2. In the early stages of development in any position the trans- 
planted buds give e^'idence of their constitution by growmg out 
