Miscellaneous. 149 



On the Regeneration of the Limbs in the Axolotl (Siren pisciformis). 

 By J. M. Philipeaux. 



On the 24th of September, 1866, I had the honour to bring before 

 the Academy some experiments demonstrating that the Hmbs of the 

 newt (Ti'iton crisfatus) are only regenerated when at least the basal 

 part of these members is left in its place (that is to say, the sca- 

 pnla, when, as in my experiments, we have to do with the anterior 

 limbs). It appeared to me necessary to repeat these experiments 

 upon other animals of the same class, in order to see whether we 

 have to do in this case with a constant fact, as, indeed, everything 

 would lead us to suppose. 



By the kindness of M. Dumeril, I have had at my disposal ten 

 Axolotls bred in the menagerie of reptiles at the Museum of Natural 

 History. On the 4th of October, 1866, I removed the left anterior 

 limb, including the scapula, from five of these Axolotls ; from the 

 five others, on the same day, I amputated the right anterior limb, 

 with scissors, at the surface of the body, consequently leaving in 

 place not only the scapula, but also the head of the humerus. 



It is now more than eight months since the operation was per- 

 formed ; and it is easy to prove that it has furnished the results 

 which I had foreseen. In the Axolotls of the first series cicatrization 

 has taken place in the most regular manner ; but there has not yet 

 been the least indication of any regeneration. In those of the second 

 series, on the contrary, very soon after the operation, the cicatrix 

 began to rise, and there was formed a projection which has gradually 

 increased, and I was able to trace day by day the phenomena of the 

 regeneration of the limb. Already, and indeed for a long time 

 past, this limb has been completely reproduced, with all its normal 

 characters of form and structure. 



Thus all the experiments which I have made since I commenced 

 studying the question of the reproduction of removed parts con- 

 stantly lead me to the same conclusion. Whether we have to do 

 with the removal of entire limbs, as in the Batrachia, or with that 

 of more deeply seated organs, such as the spleen in the Mammalia, 

 regeneration never takes place except when the operation has left in 

 position, and with its normal anatomical connexion, a portion of the 

 limbs or of the spleen. This constancy in the results already at- 

 tained has encouraged me to try other experiments, the results of 

 which I will hereafter communicate to the Academy. — Cotnptes 

 Rendus, June 10, 1867, p. 1204. 



On the Development of the Brown Aphis of the Maple. 

 By MM. Balbiani and Signoret. 



The facts recently observed by M. Dareste in the evolution of the 

 common fowl, and the deductions which he has drawn from them 

 with regard to the production of races in animals, with the conclusive 

 analogous examples in plants made known by M. Naudin, demon- 

 strate that, in both kingdoms, certain anomalies of development may 



