Chap. XXYII. OF PANGENESIS. 385 



nascent cells, together with the superabundance of the gem- 

 mules derived from both parents, and the subsequent self- 

 multiplication of the gemmules, throws light on a widely 

 different group of facts, which on any ordinary view of 

 development appears very strange. I allude to organs which 

 are abnormally transposed or multiplied. For instance, a 

 curious case has been recorded by Dr. Elliott Coues 58 of a 

 monstrous chicken with a perfect additional right leg articu- 

 lated to the left side of the pelvis. Gold-fish often have 

 supernumerary fins placed on various parts of their bodies. 

 When the tail of a lizard is broken off, a double tail is some- 

 times reproduced ; and when the foot of the salamander 

 was divided longitudinally by Bonnet, additional digits 

 were occasionally formed. Yalentin injured the caudal 

 extremity of an embryo, and three days afterwards it 

 produced rudiments of a double pelvis and of double hind- 

 limbs. 59 AYhen frogs, toads, &c, are born with their limbs 

 doubled, as sometimes happens, the doubling, as Gervais 

 remarks, 60 cannot be due to the complete fusion of two 

 embryos, with the exception of the limbs, for the larvae are 

 limbless. The same argument is applicable 61 to certain 

 insects produced with multiple legs or antennas, for these are 

 metamorphosed from apodal or antennas-less larvae. Alphonse 

 Milne-Edwards 62 has described the curious case of a crusta- 

 cean in which one eye-peduncle supported, instead of a com- 

 plete eye, only an imperfect cornea, and out of the centre of 

 this a portion of an antenna was developed. A case has been 

 recorded 63 of a man who had during both dentitions a double 

 tooth in place of the left second incisor, and he inherited this 

 peculiarity from his paternal grandfather. Several cases are 

 known 64 of additional teeth having been developed in the 

 orbit of the eye, and, more especially with horses, in the palate. 



58 'Proc. Boston Soc. of Nat. Hist.,' de l'Homme,' &c, 1862, p. 129. 

 republished in ' Scientific Opinion,' e2 Giinther's ' Zoological Record, 

 Nov. 10, 1869, p. 488. 1864, p. 279. 



59 Todd's 'Cyclop, of Anat. and 63 Sedgwick, in ' Meiico-Chirurg. 

 Pliys.,' vol. iv., 1849-52, p. 975. Review,' April, I860, p. 454. 



6 "° ' Compte Rendus,' Nov. 14, 1865, , 64 Isid. Geoffroy Saint-Hilaire, 



p. 800. 'Hist, des Anomalies,' torn i., 1832 



61 As previously remarked by pp. 435, 657 ; and torn. ii. p. 560 

 Quatrefages, in his ' Metamorphoses 



