140 S. R. DETWILER 
Reduplication of the limb rudiment was not accompanied by 
a reduplication of the shoulder-girdle, there being only one girdle, 
which, however, was reversed and in which there occurred two 
glenoid cavities, one for each member of the reduplication. 
Braus (’09) claimed from his experiments on Bombinator that 
when reduplicating limbs arose from a single transplant, there 
occurred a corresponding reduplication of the shoulder-girdle— 
observations on which he partly based his conclusions that the 
shoulder-girdle, like the limb, constitutes an equipotential 
system. From the case (AS4:2) under consideration as well as 
from cases previously reported (Detwiler, ’18), it can be said 
that reduplication of the limb in Amblystoma is not accompanied 
by reduplication of the shoulder-girdle. 
The shoulder muscles to the anterior disharmonic lmb in 
case AS4,. were normally developed and were well supplied with 
nerves, while the shoulder muscles to the harmonic limb showed 
marked deficiencies and no muscular differertiation whatsoever 
had taken place in the arm. No nerves ccald be traced to the 
limb. 
Case AS45. In this specimen (fig. 13), preserved sixty-eight 
days after the operation, the transplanted limb was innervated 
_by a plexus of nerves coming from the fifth, sixth, and seventh 
segments of the cord (table 2 and fig. 10). Limb reflexes in this 
case began about six days later than did those in the normal 
intact limb of the left side, although perfect codrdinated function 
was not attained until fifteen days later. The shoulder mus- 
culature was typically developed (table 3) except for a rather 
short m. procoraco-humeralis, the result of an imperfect develop- 
ment of the coracoid. 
The shoulder muscles were well supplied with peripheral 
nerves, as were also the muscles of the limb itself. Figure 2 
represents a graphic reconstruction of the left normal brachial 
plexus of case AS4s5._ Figure 10 is a reconstruction of the plexus 
supplying innervation to the transplanted limb which was 
centered ventral to the eighth myotome. The tendency for 
transplanted limbs to be innervated by nerves coming from 
segments of the cord situated anterior to the limb itself is well 
illustrated in this figure. 
