358 ANNALS NEW YORK ACADEMY OF SCIENCES 



a diphycercal tail Avithout powerful rays^ such as might be found in an 

 ancestor of the branchiosaurs. 



The endoskeleton of the pectoral limb of the Ehipidistia offers the 

 only remote approach to the tetrapod type hitherto known among recent 

 or fossil types. As far back as 184.3 James Hall described the pectoral 

 limb of a large fish from the Catskill formation (Upper Devonian) of 

 Blossburgh, Pennsylvania, and named it Sauripierus in allusion to the 

 ^'sauroid^^ form of the limb. In 1908 my colleague Dr. Hussakof pub- 

 lished a small photograph of this specimen in his Catalogue of Types 

 and Figured Specimens of Fossil Vertebrates in the American Museum 

 of N'atural History, Part I, Fishes (p. 59). As I had long been par- 

 ticularly interested in the problem of the origin of the Tetrapoda I was 

 impressed by the almost stegocephalian "look'' of the pectoral limb of 

 SauripteruSj and in February, 1911, I read a paper before the New York 

 Academy of Sciences entitled "The Limbs of Eryops and the Origin of 

 Paired Limbs from Fins" (1911) in which I proposed to homologize the 

 ascending blade of the shoulder-girdle of Sauripterus with the scapu- 

 iocoracoid of Eryops, the single basal element of the fin with the humerus, 

 the two following elements with the radius and ulna and the remaining 

 osseous pieces with the carpus and digits. In September, 1912, my 

 friend Dr. Bertram G. Smith (1912, pp. 540-547) prefaced his excellent 

 discussion of the phylogeny of the urodeles with a summary of my 

 Columbia University lectures on the origin of the Amphibia, in which a 

 Saw%pterus-like type of pectoral was assumed as the starting point for 

 the cheiropterygium ; a sketch of the Sauripterus pectoral, by Dr. Hus- 

 sakof, served to illustrate the subject. In the same year. Professor Patten, 

 in his book "The Evolution of the Vertebrates and their Kin" (p. 390), 

 reproduced a photograph of an excellently preserved pectoral limb of 

 Eusthenopteron (Fig. 8) and said: "Within the pectoral fins, for the 

 first time in the phylogeny of the vertebrates, appears an axial skeleton 

 that approaches, in the arrangement of its elements, the characteristic 

 structure of the appendages of the land vertebrates, i. e., Eusthenopteron/' 

 In his diagram he homologized the various elements of the fin with the 

 humerus, radius, ulna, carpus, metacarpus and digits, in much the same 

 way as I had done in the case of Sauripterus. Early in 1913, Mr. D. M. 

 S. Watson published in the Anatomischer Anzeiger a note "On the Prim- 

 itive Tetrapod Limb" in which he also took the Eusthenopteron pectoral 

 as a starting point for the cheiropterygium and regarded it as a "reduced 

 archipterygium." In September, 1913, Dr. Broom in his paper "On the 

 Origin of the Cheiropterygium" gave sketches of the pectoral paddles 

 of Eusthenopteron and Sauripterus and of the shoulder-girdle of the 



