TRANSPLANTATION OF LIMBS IN AMBLYSTOMA 123 
With the above possibilities in mind it became necessary, for 
proper interpretation of the results, to make a study of the normal 
anatomy and the normal conditions of innervation. The brief 
description which is herewith presented is based upon a study of 
a series of cross-sections (10u) of a specimen preserved seventy 
days after the closure of the medullary folds. This has been 
augmented by a dissection of the shoulder region of an adult 
specimen. 
A. Shoulder-girdle 
A description of the cartilaginous girdle as found in a larva 
twenty days after the closure of the neural folds has previously 
been given (Detwiler, 718, p. 501, and fig. 23). The conditions 
found in a larva of seventy days do not show fundamental alter- 
ations in general topography. The suprascapula has extended 
its growth somewhat more dorsal and has lengthened out in an 
anteroposterior direction so as to form a flat plate of cartilage. 
The procoracoid has expanded in an anteroventral direction and 
the coracoid has undergone a ventral expansion so as to overlap 
its counterpart in the midventral line. The scapula has under- 
gone partial ossification and that portion of the procoracoid 
which enters into the formation of the glenoid cavity, although 
still cartilaginous, is about to undergo ossification. This is sug- 
gested by the greatly enlarged cartilage lacunae in that region. 
The adult shoulder-girdle is illustrated in figure 1. The entire 
scapula, together with those portions of the procoracoid and the 
coracoid which enter into the formation of the glenoid fossa, 
have become ossified. The greater part of the procoracoid and 
coracoid and also the entire suprascapula remain cartilaginous 
throughout life. 
B. Shoulder muscles 
So far as could be ascertained, no description of the shoulder 
muscle of Amblystoma appears in the literature. The muscu- 
lature, however, so far as has been studied, closely resembles 
that of Salamandra, a European tailed Amphibian described 
THE JOURNAL OF EXPERIMENTAL ZOOLOGY, VOL, 31, No. 1 
