AMPHIBIANS. 85 



4. A bone (32 1 ) has been universally recognised as analogous to the coracoidian clavicle [coracoid] 

 of Birds, which, enlarged at its extremities, articulates by the intermediation of the preceding with the 

 coracoid apophysis of the scapula [post-scapula], approximates within to its congener, find appears to 

 sustain the posterior part of the Sternum [(rue sternum]. The first of these connections would be 

 sufficient, were fresh proofs required, to justify the name of coracoid bone given to this bone by Cuvier, 

 Geoffrey, &c. 



5. Running parallel to the preceding bone we see, in front of the Shoulder, another bone 

 [prce-coracoid] , (No. 32 3 ), which articulated with the acromion apophysis of the scapula \pr(B-scajwla\ 

 approximates by the other extremity to the anterior part of the Sternum, without, however, as has been 

 supposed, articulating with it. This bone, straight in the Frogs and Toads, very arched in the 

 Rainette, the Sonneurs, and the Accoucheurs, is designated by every one the furcular clavicle (fourchette), 

 and is compared to the furculum of Birds. It is even indicated as such in the figures of M. GeofFroy 

 (' Phil. Anat.,' pi. ii, fig. 22), although in other Reptiles this learned zoologist had exactly determined 

 and designated, under another name, its true analogue. We believe it to be the " acromial " [it is the 

 prtz-coracoid] ; it is the acromial [clavicle'] of Lizards (1. c., fig. 23) and of the Ornithorhynchus 

 (ib., fig. 19), a bone which in certain Mammals has already attained a great size, although still confused 

 with the acromion (Sloths). 



6. The true furculum [pr<e-epicoracoids] or furcular clavicle (No. 34 s ) is the piece regarded as 

 sternal by some, and as belonging to the Shoulder, but without precise determination by others 

 (Cuvier, Meckel) . That which has caused it to be regarded as a dependency of the Sternum is that it 

 has not been known in its whole length, because it long remains cartilaginous, and is even always of 

 soft consistence, so that it becomes deformed by desiccation ; moreover, its horizontal branch is masked 

 by the preceding piece. An exact idea of this right-angled clavicle will easily be obtained from our 

 figures (they fail to show the mesial divisional line), of which the transverse branch extends as far as 

 the paraglenal bone [semi-osseous synchondrosis'], and is even extended to it whilst the cartilaginous 

 condition is still complete, whilst the antero-posterior serves as an intermediary piece between the 

 acromial \_pr<z-scapula\ and the coracoidian \coracoid~\, often very elongated (Toad, fig. 26), and even 

 prevents the bones of this name from touching one another in the middle line. It is not less remark- 

 able that to it alone belongs the connections of the Shoulder with the Sternum, as may be seen in 

 figs. 22, 23, 25. The furculum [pree-epicoracoidii] remains cartilaginous amongst the Rainettes and the 

 Sonneurs ; it only ossifies very late and imperfectly in the Toads ; but in all these species, and especially 

 in the Bomblnator (fig. 15) its antero-posterior branch is much enlarged : moreover, that of one side 

 constantly crosses that of the other, the right being generally the more superficially situated. In 

 the Frogs (figs. 22, 23, 31) the furculum [prte-epicoracoids], more osseous, and having at least the same 

 consistence as pasteboard, or as the white part of a feather of a Bird, does not offer this enlargement 

 of the antero-posterior branch, nor the above-mentioned crossing. These two cartilages, even at an 

 early period, unite on the median line ; there results, consequently, an azygous bone [symmetrical 

 bars, partly confluent in the young of Bufo vulgaris ; see my figs. 15 and 16 in Plate V~\ in the 

 form of a T, of which only the longitudinal part has been known (Cuvier, ' Oss. Foss.,' t. v, p. ii, 

 pi. xxiv, fig. 31, ), and that has been supposed to be wanting in Toads. It has thus happened that 

 M. Geoffroy has called it an entosternal (' Phil. Anat./ pi. ii, fig. 22, ), whilst others have thought 

 that the Frogs were deficient in the cartilages recognised in the Toads by reason of their great develop- 

 ment (Meckel). Let us anticipate the objections that may be adduced against my determinations of 



1 See Plate V, fig. 11, cr. * See Plate V, fig. 11, p. cr. 



3 See Plate V, figs. 6, 9, 11, 15, 16, p. cr., e. cr. 



