Coues.] 80 [May 13, 



the middle one dragged on the ground, and the hind one was elevated 

 behind ; but it continually fell over on its left side. 



The supernumerary legs were not merely offshoots from the nor- 

 mal one, or dangling by tegumentary attachments ; but were entire, 

 movable from the hip-joints, and apparently provided with all the 

 ordinary muscles; but from some defect in the articulations, or want 

 of voluntary control over their muscles, they were functionless, and, 

 indeed, decidedly worse than useless. They were clothed with skin 

 and feathers to the usual point (tibio-tarsal joint), and projected out- 

 side the common integument of the body as far up the thighs as the 

 normal legs did. The middle left leg was bound by common integu- 

 ment to the anterior one as far as the heel; the posterior left leg was 

 freely isolated. The right leg was perfect in every respect ; the left 

 one corresponding to it (anterior one of the three) was as large, and 

 equally perfect, except in a slightly increased stiffness and basal ad- 

 hesion of the anterior toes ; the sole of this foot rested on the ground 

 in normal position. The middle left leg (anterior supernumerary one) 

 was scarcely shorter, and very nearly as stout; it dangled close be- 

 hind and reached the ground, but was twisted half around by great 

 eversion of the thigh, so that the knee pointed outward instead of 

 forward, and the heel inward, while stiffening, or other defect of the 

 tibio-tarsal joint, caused the metatarsus to project nearly horizontally 

 outwards. The toes of this leg were permanently stiffened, flexed 

 and drawn together; and in consequence of the direction of the 

 preceding segments, their outer sides instead of their plantar sur- 

 faces were opposed to the ground; and all the claws, the hind one 

 included, pointed forward and outward. The anterior claws, however, 

 would have pointed backward could they have been outstretched. 

 The third or posterior (second supernumerary) left leg was stunted as 

 well as misshapen. It projected far backward, almost under the tail, 

 and was permanently so much flexed at knee and ankle that the toes 

 did not touch the ground. The flexures and direction of the seg- 

 ments of this leg were all normal; the foot and toes perfect in shape 

 and relative proportions. Its chief peculiarities were its permanent 

 flexion and its general marasmic condition — the stunting affecting 

 bones and muscles alike. Corresponding to this atrophied condition 

 was a lack of pigmentary matter in the scaly parts of the leg; these 

 being yellowish flesh color, while the other three legs were dusky. 

 When the chick moved about, this posterior leg spasmodically sawed 

 the air in the vain attempt to coordinate its motions with those of 



