LIFE AND KINSHIP OF DINOSAURS. 601 



To return, however, to my proper task, more especially in reference to the affinities of 

 the Dinosauria. 



The first clue to the homology of the supposed clavicular bone of the Iguanodon* was 

 given by Professor Leidy in the ' Proceedings of the Academy of Natural Sciences of 

 Philadelphia,' December 14th, 1858. In the description there given of the fossil remains 

 of a Reptile, which he calls ' Iladrosaums,' from the marl of New Jersey, which marl, 

 from the affinity of this Reptile to the Iguanodon, he surmises may be of the Wealden or 

 Green-sand period, Leidy finds, with the ilium, "a bone which I suspect to be the 

 pubic, but which appears to correspond with that of the Maidstone Iguanodon, described 

 as the clavicle" (p. 9). In a subsequent illustrated Monograph.t Leidy repeats 

 his homology of the bone in question and notes — " an ilium and a supposed pubic 

 bone, imperfect" (p. 71). Of the latter a figure is given (" PI. VIII, fig. 13 "), and the 

 accomplished Author truly remarks : — " It bears a general resemblance to that indicated by 

 Professor Owen and Dr. Mantell as the clavicle of the Iguanodon ; but appears to me 

 rather to resemble the pubic bone of the Iguana and Cyclura than the clavicle of the 

 same animals.";}: 



Professor E. D. Cope, Corr. Sec. Academy of the Nat. Sciences, Philadelphia, commu- 

 nicated to the Academy, in 1867, a paper "On the Extinct Reptiles which approached 

 tlie Birds," of which an ' Abstract' was given in the ' Proceedings of the Academy ' for 

 December of that year. In this 'Abstract' the Professor is reported as stating that " he 

 was satisfied that the so-called clavicles of Ic/uanodon and other Dinosauria were pubes, 

 having a position similar to those of Crocodilia."§ There is no reference, therein, to 

 Professor Leidy, nor to the paper by Professor Huxley " On the Classification of Birds " 

 which was published in the ' Proceedings of the Zoological Society,' 1867, p. 415. || 



In the lecture " On the Animals which are most nearly Intermediate between Birds 

 and Reptiles," delivered by Professor Huxley at the Royal Institution of Great Britain, 

 7th February, 1868, he states: — "I hold it to be certain that these bones — the so- 

 called ' clavicles ' — belong to the pelvis and not to the shoulder-girdle, and I think it 

 probable that they are ischia ; but I do not deny that they may be pubes." 



Thanks to the rapidity by which, through science, sea and land can now be traversed, 

 we get the results of research by our American fellow -labourers within a fortnight, usually, 

 after publication. 



I have no doubt of the legitimacy of Professor Huxley's delusion — " I could not 

 possibly have known anything about them when my ' Lecture' was delivered ;" but 



* 'Philos. Trans.,' p. 138, 1841. 



t 'Cretaceous Reptiles of the United States,' p. 97, pi. viii, fig. 13 : in the 'Smithsonian Contribu- 

 tions to Knowledge,' No. 192, vol. xiv, 4to, 1865. 

 X Op. cit., p. 97. 

 § • Proceedings of the Academy of Natural Sciences of Philadelphia,' p. 234, 8vo, 1867. 



II See " Note," p. 24, in ' Quarterly Journal of the Geological Society of London,' vol. xxvi (18/0). 



