TRANSPLANTATION OF LIMBS IN AMBLYSTOMA 139 
rudiment centers ventral to the eighth somite, results in still 
greater decrease in the number of cases with normal limbs, and 
a corresponding increase in the number of cases in which redupli- 
cation of the rudiment occurred (table 1a, series AS4). Seventy- 
nine per cent of limbs so transplanted became functional, al- 
though only 41 per cent exhibited perfect movements, the func- 
tion of the remaining 38 per cent being impaired in one way or 
another (table 1a, series AS4 and fig. 8). 
The transplanted rudiments of this series, although placed 
ventral to the seventh, eighth, and ninth somites, became inner- 
vated by plexuses derived mainly from segments situated anterior 
to those corresponding to the position occupied by the limb 
rudiment, as was found to be the case in the series already de- 
scribed. The segmental nerve supply, although preéminently 
coming from the fourth, fifth, and sixth segments, exhibits some 
variation, as is shown in table 2. In case AS44 (fig. 14) the rudi- 
ment developed into a reduplicated appendage, the anterior 
disharmonic member of which became fully differentiated and 
functional, while the posterior harmonic member developed into 
a structurally deficient and atrophic appendage. As a conse- 
quence of reduplication, the anterior member, being nearer the 
original limb level than the posterior, was found to receive 
practically all of the nerve supply, which was contributed by 
the fourth, fifth, sixth, and seventh segments of the cord (table 
2, case AS4,,). 
The anterior (disharmonic) member in this case did not begin 
to develop until eighteen days after the operation. At this 
period it began as a small knob-like growth on the radial side 
of the base of the harmonic limb, which up to this period had 
developed normally. The reduplicating bud developed with 
marked rapidity, and eleven days later it had differentiated into 
a normal appendage and had become functional. From this 
time on it rapidly improved in growth and function, while the 
posterior harmonic limb underwent gradual atrophy. ‘The rel- 
ative size of the two limbs at sixty-four days after the operation 
is shown in figure 14. | 
THE JOURNAL OF EXPERIMENTAL ZOOLOGY, VOL. 31, No. 1 
