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these muscles, the shoulder becomes, as it were, freed from its an- 
chorage, the respiratory movements of the animal are seriously impeded. 
In man, in whom the respiratory movements of the upper chest 
are perhaps less pronounced, the respiratory function of the trapezius 
is not so prominent: though as I have pointed out, it remains of 
considerable importance and indeed may be paramount in cases of 
paralysis of the spinal nerves to chest and diaphragm. 
The tonic action of the trapezius in maintaining the position of 
the shoulder is of considerable importance both in the mammals 
already considered and in man. In animals paralysis of this muscle 
causes impairment of the normal movements of the fore limb with 
a certain amount of ataxia and results in the falling back of the 
shoulder girdle on the chest. 
In previous communications I have discussed this subject at some 
length. (7) (8) Figs. I and II will therefore suffice to show the 
alteration in position of the shoulder girdle in the giraffe which 
formed the subject of one of the previous papers. 
In man, the falling of the shoulder which results from paralysis 
of the trapezius, has less effect on respiration, and on movements of 
the fore-limb than in pronograde animals. It may, however, give 
rise to the appearance of symptoms such as were exhibited in the 
case of A. 8. to which reference has been made at the commencement 
of this communication. 
These occur as a result of the dragging downwards of the 
shoulder by the weight of the arm and they are directly produced 
by mechanical lesions in the Sth and 6th cervical nerves. 
The same symptoms may be produced by a temporary loss of 
tone in the trapezius and such instances are represented by the case 
recorded by Professor GEDDES. 
In like manner, the symptoms of “cervical” rib may first appear 
during the convalescence from influenza, while the general lack of 
muscular tone consequent on that disease is still present. 
It would be beyond my province to enter more fully into clinical 
details. I therefore remain content with giving the foregoing account 
of the anatomy underlying the cases already mentioned. 
I would in conclusion acknowledge my indebtedness to Professor 
ARTHUR Kita of London for his suggestions concerning the human 
portion of this paper, and to Messrs. Jennison and Mr. Bamey of 
Belle Vue Zoological Gardens for the opportunity of obtaining facts 
concerning their animals. 
