
No. 427.] ABNORMALITY IN CATS’ PAWS. 523 
A comparison of the indices and the weights of the indi- 
vidual bones of both the normal and abnormal manus is shown 
in the accompanying table. For the purpose of more accurate 
comparison of the two sets of bones, I have figured the per- 
centage which each bone bears to the total weight of all the 
bones of the manus to which it belongs (including ulna and 
radius). The indices of the bones were obtained by finding 
the ratio between the minimum thickness and the maximum 
length of each bone. The actual points of measurement are 
shown by the dots in Fig. 17, ZZZ. Inspection of the bones 
first leads us to see that digit A (Fig. 18) is much longer than 
the normal pollex and presents in the undissected manus more 
the character of a finger than of a pollex. The bones, however, 
are distinctly those of a pollex, since there are two phalanges 
only; but they are longer and more slender. In this respect 
they resemble a finger. The bones of digit B (Fig. 18) are more 
like a pollex than are those of the digit which normally adjoins 
the pollex. One can also see that digit C (Fig. 18) is more 
like a pollex than is the digit which is normally fourth from the 
ulnar side. What further facts are there to bear out the idea 
that where there are normally two digits, there abnormally occur 
three, each of which partakes somewhat of the general charac- 
ters of the others ? 
It is a fact that where normally two digits are found, namely, 
a pollex and an index, there are found in this special case 
three, and that the material which would normally form two 
digits has so distributed itself that each of the three digits 
which actually occurs partakes of the nature of the other two. 
Is the abnormal pollex two-thirds pollex and one-third index ; 
the digit next the pollex, one-half index and one-half pollex ; 
and the digit C (Fig. 18) two-thirds index and one-third pollex? 
There seems to be some relation of this sort. 
If we compare the indices and the relative weights of the 
two manus, we come to a like conclusion (see accompanying 
table). For example, comparing the percentages of total 
weights in the abnormal manus, metacarpal A (Fig. 18) is more 
like the other metacarpals of its manus than is metacarpal 7 of 
the normal manus like the other metacarpals of its manus; 
