56 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 
Appendicular Skeleton. 
In Typhlomolge, two of the most striking characteristics are the 
length of the limbs and the delicate structure of the bones of the 
limbs and girdles. In these it differs widely from Necturus, Axolotl, 
and the majority of the Salamandrids, which have short, heavy, 
thickset bones, and resembles Proteus, though carrying lightness 
and length of bones to an even greater extreme, a similarity which 
is correlated with their similar mode of life. The number and 
arrangement of the carpal and tarsal elements and the number of 
digits, four on the anterior and five on the posterior limb, are, how¬ 
ever, much more suggestive of the Salamandrids than of the Pro- 
teidae, and the square shape of the pelvis is much more like that of 
Spelerpes than like the attenuated form found in Necturus and 
Proteus. 
Pectoral Girdle and Anterior Limb. 
In Typhlomolge, the general plan of the pectoral girdle is like that 
of the other IJrodeles. It consists of two lateral plates, largely car¬ 
tilaginous and quite free from each other and from the axial skele¬ 
ton, although one overlaps the other slightly in the mid-ventral line. 
Each plate, which lies close to the trunk muscles, consists of three 
thin lobes radiating from the glenoid fossa, the dorsal one being the 
scapula, the antero-ventral the procoracoid, and the postero-ventral 
the coracoid. 
The ventral portion of the scapula, a narrow shaft, widening 
slightly at each end, is the only bony portion of the girdle, and 
this is continuous with a broader, dorsal, cartilaginous portion, its 
dorsal border being opposite the lateral process of the third and 
fourth vertebrae. 
The procoracoid is nearly as long as the scapula, but more slender 
and very thin, tapering anteriorly to a blunt point. 
The coracoid is oval in shape, its posterior border slightly poste¬ 
rior to the shaft of the scapula, and its anterior half lying nearly 
parallel with the posterior half of the procoracoid. The cartilage 
about the glenoid fossa is thickened, forming a strong rim about the 
cavity. 
The humerus in Typhlomolge is very long and slender. Its 
