1867.] 263 [Wyman. 



If it bo true, as he says, that the shoulder is the pelvis reversed, then 

 it follows that the part of the latter Avhich is farthest backwards, viz., 

 the ischium, would be repeated in the shoulder by the clavicle, which 

 is farthest forwards. This arrangement of the parts would be in ac- 

 cordance with the idea of symmetry, and Avith which M. Martins' 

 description certainly does not agree. 



Mr. Humphrey's determination of the parts, though based upon 

 use and not upon the idea of symmetry, is strictly in accordance with 

 it ; the hinder edge of the scapula, according to him, being repeated 

 in the fore edge of the ilium, the coracoid in the pubes, and the clavi- 

 cle in the ischium. 



Foltz adopts a method of viewing these parts quite different to 

 that of either of the authorities alluded to above, but not unlike that 

 made use of by Cruveilhier, and also by Martins, as will be seen fur- 

 ther on, who compare a portion of one and the same bone in one limb, 

 to two different bones in the other. The body of the pubes, according 

 to Foltz, corresponds with the coracoid process of the scapula, while 

 the descending branch corresponds with the clavicle.* He seems to 

 overlook the tact that the body and descending branch are all of one 

 piece, are ossified from a single centre, and never show themselves in 

 any other way. Under these circumstances they cannot be consid- 

 ered other than as parts of one and the same bone, imless all ideas of 

 the individuality of bones are abandoned. Following the principles 

 of symmetrical development already laid down, the homologous parts 

 will stand as follows : — 



Scapula, Fig. 6, a Ilium, Fig. 7, A. 



Clavicle, " b Ischium, " b. 



Coracoid, " c Pubes, " c. 



Limbs. The general homology of limbs, as has also been the case 

 with the scapular and pelvic arches, has attracted much less attention 

 than the special. Oken regarded them as " liberated ribs." In this 

 view he has had but few followers, tliough Maclise in the article " Skel- 

 eton" in the Cyclopaedia of Anatomy and Physiology, advocates some- 

 what at length a similar interpretation of these parts. Limbs are 

 more commonly spoken of as " appendages" to their respective arches, 

 and as "diverging appendages" by Owen, who at the same time con- 

 siders them as serially homologous with the " oblique processes " on 

 the ribs of birds, crocodiles and most fishes. With regard to the ob- 

 lique processes just referred to, he suggests that while such rudiment- 

 ary limbs in these animals never come to be more than spines attached 

 to the edges of the ribs in the actual vertebrates, they might po.=sibl',' 



* Homologie des Membres Pelviens et Thoraciques. Par le Docteur Foltz. Jour- 

 nal de Physiologic. Paris, 1863. T. vi, p. 53. 



