1881 .] 
171 
[Kingsley. 
Balsamo Crivelli describes 1 three instances in Rana escnlenta, 
in one the pelvis is entirely normal and the additional member is 
in close relation with the left femoral articulations. A second 
has a leg inserted on the left side in the vicinity of the symphysis 
pubis which has the appearance of resulting from the fusion of 
two legs. In the third case the supernumerary member is borne 
on the right side. The anatomical details in each case are very 
few. 
M. Lunel describes two instances in the common green frog 
of Europe. In the first we have a frog in which the usual single 
anterior leg of the left side is replaced by three. The shoulder 
girdle is normal until we come to the scapula which is divided 
into three parts and with each articulates a humerus. Beyond 
this each division or arm is modelled after the usual pattern. In 
the second instance we have two additional pairs of legs arising 
from the left side, well formed and nearly of the usual size. The 
pelvic arch shows on the left of the principal pelvis an incomplete 
one with confused traces of the pelvic bones and a single rudi- 
ment of an iliac portion 50 mm. in length. By the strain of these 
appendages the principal pelvis is twisted in its upper third and 
the symphysis is removed from its proper position. M. Lunel 
mentions a third case of additional j^elvic members which M. 
Ducret proposes to describe but I have been unable to find that 
he has done so. 
In 1878 8 I mentioned the existence of the present specimen, 
and during the same year Mr. Ryder 11 describes, from a drawing 
by the late Jacob Stauffer, a frog with an extra hind limb bearing 
evidences that it was formed by the fusion of two by their inner 
faces. 
The specimen which it is my lot to describe belongs to the 
Lyceum of Natural History, a students’ society in W illiams College, 
Williamstown, Mass. It is the form known as Rana halecina and 
is badly faded from its long immersion in alcohol. Of its history 
I can obtain no information except that conveyed by the faded 
label : “ Rochester, N. Y.” It has been in the possession of the 
Lyceum for over thirty years. 
The body is two and a quarter inches in length, and the two 
normal hind legs are well developed but are slightly different in 
