Pectoral Fin 0/ Eiistlicnoptcron. 



475 



does not entirely confirm the theory of Gegenbaur, according 

 to which the tetrapod limb is derived from a reduced uniserial 

 archipterygium (com p. Gegenbaur, 1898, p. 520), but never- 

 theless it is more in conformity with this tlieory than with 

 the other (also advocated by Watson), which takes a reduce 1 

 biscrial archipterygium for the base of the tetrapod limb. 



Fie 



Tlie internal skeleton of the Pectoral Fin of Eusilienop/eron, showirg 

 homologies with the tetrapod limb. Nat. size. 



fill., humerus ; «., ulna ; r., radius; ul., ulnare ; p., pisiform ; ca., three 

 distal carpalia; I.-V., digits ; ax., axis of the tetrapod lijub. 



Tn conclusion, T desire to express my thajiks to Dr. Smith 

 Woodward for the loan of the new prepaiatioii and lor 

 valuable help. 



Literature. 



1. J. F. WniTRATES. "Illustrations of the Fossil Fishes of the Devonian 



Rocks of Canada,'' in Trans. Roy. Soc. Canada, vol. vi. 1889, 

 p. 77 seq. (on Eusthennptcron, p. 78 scq.). 



2. R. H. Traquair. "Notes on the Devonian Fishes of Scaumenac 



Ray and Campelltown in Canada," in Geol. jMag. vol. vii. 1890, 

 p. lo seq. (on En.'ifJienopieroii, p. 18 seq.). 



