86 SHOULDER-GIRDLE AND BREAST- BONE. 



the parts forming the Shoulder in many Reptiles and in the Monotremes. Amongst these, as 

 amongst the Sauriaus, there exist two pieces, obviously comparable with our furcular clavicles [pr<e- 

 epicoracoids] , and which are designated as a double episternal by M. Geoffrey (1. c., pi. ii, figs. 19, 

 20, 23, 1. 1.), as pieces of the Shoulder not yet determined by Cuvier (' Oss. Foss./ t. v, 1, p. xiii and 

 xiv, m. m., and pt. ii, pi. xvii d. d.). If the relations of these pieces with the other bones of the 

 Shoulder and of the Sternum do not suffice to enable us to recognise them as furcular clavicles [prce- 

 epicoracoids], the way of exclusion conducts us to it necessarily. In effect 1. In the ideas of 

 M. Geoffroy the true furculum would be this bone (in the form of a T, or of a cross) that Cuvier has 

 marked n, f, /, for the Ornithorhynchus, a for the Saurians (figs, mentioned). But, according to 

 Cuvier, a part only of the Sternum was recognisable in this bone amongst the Monotremes ; 

 he compares it to the first piece of the Sternum in the Kabasson, to which we may add many 

 other Mammals [in these there is no inter-clavicle, but a produced manubriuni], which have their 

 first piece \manubriuni] very much enlarged. Amongst the Saurians it is related quite naturally to 

 the episternum of the Crocodiles [inter-clavicle] , (plate v, fig. 5), a piece recognised as episternal, 

 even by M. Geoffroy ('Phil. Anat./ t. i, p. 213), and which represents perfectly the T [inter-clavicle'] 

 of the Tupinambis (Monitors), the cross [inter -clavicle] of the Lizards, and the anterior part of the 

 Sternum (omosternum) of the Anourous Batrachians. In fact, under this last relation, the analogy is 

 supported by the advanced position and flat form of the Crocodilian piece [inter-clavicle} of which we 

 are now speaking; only it is in relation with the other parts of the Sternum [true Sternum], which 

 does not take place amongst the Batrachians. Supposing that in the Ornithorhynchus [the epicoracoids] 

 and the Lizards the furcular pieces [prce-epicoracoids] approximated to one another as in the Frogs, and 

 the episternal [inter-clavicle'] pushed forward, and thus separated from the rest of the Sternum [true 

 Sternum], and \ve should have an evidently complete analogy ; we should even be able to find in the 

 handle of the posterior Sternum of the Toad (Crapaud catamite) the representative of the two pieces 

 of the entosternal (o) of M. Geoffroy; and as to the remainder of the Shoulder, the comparison will 

 be still more easy in holding to the determination of the latter author, excepting only his supposed 

 furcular [inter-clavicle] and his episternal [pra -epicoracoids] bones, which, according to our views, 

 ought to undergo a material exchange of name. 



2. According to Cuvier, it is our acromial [pra-coracoid bar] amongst the Anourous Batrachia, that 

 of M. Geoffroy amongst the Monotremes [clavicle], and the Sauriaus [clavicle'], which is the true furculum 

 [the true furculum, i. e. of the Bird, is highly complex] ; but then we do not know to what to refer our 

 furculars [pra-coracoids], we must leave them without determination. Let us observe also that the 

 acromial [here he means the clavicle'] is often attached to the ad-scapulum [supra-scapula], as in the 

 Lizards, the Iguanas, the Scincidse, and the Orvet (Anguis fragilis), a circumstance which well accords 

 with the acromion, of which the base in Mammals reaches along the whole external surface of the 

 scapula, and not to the clavicle always attached by its free extremity. I place here, in reference 

 to the shoulder of the Anourous Batrachians, that of the " Orvet" (Anguis fragilis, fig. 27 1 ), where 

 we find the episternal [omosternum] absent, as in Toads, an osseous acromial [clavicle] attached to 

 the ad-scapulum [supra-scapula] , a cartilaginous clavicle [pr<e-coracoid], enlarged as in the bombinator, 

 obstetricans, and springing very evidently from the scapula. This last is osseous, as well as a coracoid 

 of which the form exactly resembles that of the Anourous Reptiles; and lastly, a large xiphoid 

 [ prce-sternum] , as in the Pipas. This shoulder is evidently as similar to that of the Batrachians as to 

 that of the Saurians. 



We also establish a parallel here between this portion of the skeleton of the Batrachian and the 



See Plate VIII, figs. 2, 4, 5, 6, s, sc., sc., p. cr., e. cr. 



