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specimen of Rana halednum Avith a peduncle from which two legs arise 

 directly ventral to the right fore leg. These are each about the size of 

 the left normal leg and distinctly larger than the normal leg of the 

 right side. 



In the same year Eigerman and Cox (5) described a case of 

 Baila pipiens in which the fore limb of the right side is duplicated. The 

 limb is fairly normal but passes forward through a band of the skin of 

 the floor of the mouth and is held as in a sling. In the hand the second, 

 third, and fourth digits are normal but the first is double. 



I have recently obtained two further cases of polymelous frogs in 

 both of which there is a single extra fore limb. The first of these was 

 handed to me by Professor J. P. Hill and was in other respects a 

 typical adult male tree frog, Hijla aurea. The second was obtained 

 during class-w^ork dissection in this college and appeared an ordinary 

 adult female Rana temporaria save for the supernumary limb. 



Description of the specimens. 



Specimen A. Hyla aurea (figure 1). 



The additional fore limb was attached immediately in front of and 

 slightly dorsal to the normal arm of the left side. It was thin but had 

 a well marked elbow joint and its distal end had the appearance of 



Fig. 1. Photograph of Specimen A. Hyla aurea, to show supernumary limb. 



having been removed by accident during the life of the animal and of 

 afterwards being healed over. Just dorsal to the base of the limb, below 

 the tympanic membrane, was an unusual lump on the side of the ani- 

 mal's head, this dissection showed to be due to the presence of a super- 

 numary scapula. 



This specimen had been preserved for a long while so that it was 

 very difficult to make out the musculature and as the whole arrangement 



