8 



pig or pigeon, the palsied limb continues to grow in length, but 

 it grows only very little, if at all, in thickness. When the 

 experiment is made on all the nerves of the wing in a very 

 young pigeon, it is also found that the wing grows in length, but 

 very little in breadth or in thickness. The secretion of quills 

 takes place equally as well in the palsied limb as in the other. 



The diiference in all these cases between the length of the 

 sound and that of the palsied limb or wing is never very consi- 

 derable ; nevertheless the length of the healthy parts is greater 

 than that of the paralysed parts. 



4. I have found that burns, wounds and ulcerations existing 

 in parts palsied in consequence of the section of their cerebro- 

 spinal nerves, are cured as quickly and as well as those in sound 

 parts. 



5. Atrophy is a constant consequence of the section of the 

 nerves of a limb. I have found that it supervenes not only in 

 the muscles and the bones, as J. Reid has discovered, but also in 

 the skin, which becomes evidently thinner. 



6. Krimer asserts that after the section of the nerves of a 

 limb in Mammals, the venous blood is of a bright red color like 

 the arterial blood. (Physiologische Untersuchungen, Leipzig, 

 1820, p. 138 exp. 1, and p. 152 exp. 9.) 



Long before the publication of Krimer, Arnemann had de- 

 clared that the blood appeared darker than usual in a limb on 

 which all the nerves had been cut. (Versuche iiber die Regera- 

 tion an lebenden thieren, Gottingen, 1786, t. i., p. 48.) 



Longet (Traitd de Physiologic, Paris, 1850, t. ii., B. p. 92,) 

 says that he has seen the venous blood retaining its ordinary 

 color even three days after the section of the nerves of the 

 anterior limb in dogs. 



Who is right Krimer, Arnemann or Longet ? Neither of 

 them is perfectly right. The assertion of Arnemann is entirely 

 incorrect. By experiments made on dogs, rabbits, guinea- 

 pigs and pigeons, I have found that the venous blood in palsied 

 limbs is evidently less black than it is in sound limbs. But it is 

 not true to say that venous and arterial blood in paralysed limbs 

 have the same color. It is always very easy to distinguish one 

 from the other. 



The transformation of the arterial blood into venous is not so 



