1871.] 161 [Wilder. 



/ 



us hope that his late magnificent contribution to rational homology, 

 292, may be followed by a like work upon the membra, as a sound 

 basis for all subsequent investigation. 



Cleland has published two short papers upon intermembral homolo- 

 gies, 47 and 65 ; in the first he inclines to the general views of Goodsir, 

 and in the latter makes the lower jaw serially homologous with the 

 membra; but he kindly permits me to state that he is by no means 

 satisfied with the present aspect of the question, and is even willing 

 to admit the existence of "symmetry" in certain corporeal organs ; so 

 that I venture to hope that he may yet recognize the antitropic rela- 

 tion of the membra, especially since I am now ready to agree with 

 him that the antagonism of the membral flexures in many mammals, 

 is the result of telical modifications of their primary and normal 

 condition; therefore, in spite of his previous views, and his disagree- 

 ment in detail with the muscular homologies of the others, he may 

 not object to being enumerated among those who follow Huxley in 

 basing their further investigation of intermembral homologies upon 

 the facts of comparative anatomy and embryology rather than upon 

 anthropotomy. 



ANTITROPY. 



The suggestion that a symmetrical relation or antagonism exists 

 between the cephalic and caudal regions of the vertebrate body, is 

 contained in many paragraphs of Oken's Physio-philosophy, 285, Par. 

 2114, 2242, 2951, etc., and has been since alluded to by Agassiz, 1 and 

 Dana 2 ; but these eminent naturalists have never published any di- 

 rect application of the idea to the membra, although it cannot be 

 doubted that Oken would now be among the first to adopt the anti- 

 tropical comparison, as Agassiz and Dana have privately done. 3 



The first published comparison of the membra upon the basis of 

 antitropy was that of Gerdy in 1829, 9; he appears to have been an 

 artist as well as an anatomist, and to have been thus led to look upon 

 the whole body as a symmetrical structure, whose upper and lower 

 ends repeat each other in opposite directions as do the right and left 

 sides; he began to apply this principle to the membra, but unfor- 



i Contrib. to the Nat. Hist, of the United States, Vol. I, pp. 308, 311, 312. 



2 Am. Jour. Science and Arts, Nov. 1863, p. 351. 



3 Prof. Agassiz also informs me that in Europe he noted the symmetrical rela- 

 tions between the manus and pes of the walrus, and afterward discussed the 

 whole subject in a course of unpublished lectures at the Smithsonian Institution. 



PROCEEDINGS B. S. N. H.— VOL. XIV. 11 DECEMBER, 1871. 



