THE 
AMERICAN NATURALIST 
VoL. XXIV. MAY, 1890. 281. 


THE HOMOLOGIES OF THE FINS OF FISHES. 
BY E. D. COPE. 
I. 'THE RELATION OF FINS TO LEGS. 
ae it is well established that the paired fins of fishes 
are, as a whole, homologous with the limbs of the higher ver- 
tebrates, and although many naturalists have given their views upon 
the homologies of the respective parts, the subject is yet involved in 
considerable doubt; and, as stated by Prof. Huxley in 1871, the 
basal and radial supports of the fins themselves can only be iden- 
tified in the most general way with the limb-bones or cartilages 
of other vertebrata. 
The: doctrine that the vertebrate limbs are modified ribs was 
advocated, to a varying extent and with modifications, by Maclise’ 
(1832) and Oken? (1843); while Owen? (1848) regarded them 
as diverging appendages attached to ribs, with a shoulder-girdle 
of axial origin. Professor Goodsir * (1857) considered the limbs 
as homologous with the epipleural spines of fishes, and external 
to the proper visceral wall of the body. Professor Humphrey * 
(1871) concluded that the vertical fins were of bifold origin, since 
1 Todd's Encyclopædia, Vol. IV., p. 79- Fig. 490. 
2 Lehrbuch der Natur-Philosophie, p. 330. 
3 Archetype and Homologies of the Vertebrate Skeleton. 
4 Edinburgh New Philosophical Journal, Vol. V., 1857, p. 178. 
5 Cambridge Journal of Anat. and Physiol., Vol. V. (Second Series, Vol IV.), p. 58, 
