218 



Muscles of Salamandni 



ANATOMY OF VERTEBRATES. 



Ml 



system of converging fibres 



takes its origin from the 

 scapula itself, and converges 

 to an insertion close to that 

 of the preceding. The entire 

 mass of the muscles 22 and 

 11 antagonise that, 16, lea, 

 below ; one raises, the other 

 \ depresses, and both rotate, 

 the humerus to and fro. As 

 the fore-limb gains size and 

 pOAver in higher air-breathers, 

 the muscle n seeks a more 

 extended origin, covers a 

 greater proportion of the seg- 

 meiital system of trunk- 

 muscles, acquires the name 

 of latissimus dor si, and, in 

 Anthropotomy, is classed 

 amongst the f first layer of 

 the muscles of the back.' The 

 muscle 22, becomes deve- 

 loped into f supra- ' and ( in- 

 fra-spinatus? and, perhaps, 

 also deltoides. The pro- 

 tractor scapula, arising, as in 

 Fishes, from the paroccipital, 

 noAV also derives fibres from 

 the transverse processes of the 

 first and second trunk-verte- 

 brae, and divides into two dis- 

 tinct fasciculi; one, fig. 140, 



19, is inserted into the base 

 of the scapula ; the other, ib. 



20, into the humeral end of 

 that bone. A small strip, is, 

 which tends more directly 

 to raise the scapula, arises 

 from the transverse proces- 

 ses of the third vertebra ; but 

 the muscle, 19, is that which 

 best answers to the levator 

 scapulce of Mammals. Two 



CLXXXVII. 



