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the brachio-cephalicus and had no doubt occurred when the small 

 portion of hoof broke off. 



Being at that time under the impression that the spinal accessory 

 conveyed the motor supply to the brachio-cephalic muscle in all 

 mammals, and being unable to understand how the mechanical injury 

 could damage the spinal accessory nerve, I determined to investigate 

 the muscle and its nerve supply in the ungulates. Messrs. Jennison 

 very kindly agreed to this suggestion, and the work was carried out 

 in the anatomical laboratory of the university of Manchester by my 

 brother, Mr. C. G. Todd. 



The results of our investigation will shortly be published in 

 the Anatomischer Anzeiger (1). In the course of this research we 

 found that in certain mammals there is no supply to the brachio- 

 cephalic muscle from the spinal accessory. Among our dissections 

 this condition was represented in the camel (camelus dromedarius). 

 It has also been found in the giraffe (camelopardalis giraffa) by 

 Elliot Smith (2) and by Lesbre in the Bactrian camel (camelus 

 bactrianus) (3), the Arabian camel (dromedarius) (4) and the llamas (5). 



In the animals mentioned the whole of the nerve-supply to the 

 brachio-cephalic muscle comes from the 3rd, 4th and 5th cervical nerves. 

 We made experiments on several of the larger ungulates to illustrate 

 the abduction of the limb, and found that such an injury causes 

 stretching of the cervical nerves passing to the brachio-cephalicus. 

 No damage is caused by this accident to the spinal accessory nerve, 

 as its great length protects it from injury (1). The paralysis of the 

 muscle in the giraffe in question is thus clearly accounted for. As 

 to the reason for the absence of the spinal accessory supply to the 

 muscle in these animals, Lesbre suggests that it may have some- 

 thing to do with the length of the neck (4). 



For some years Professor Elliot Smith, in his lectures to medical 

 students, has been citing the arrangement of nerves in the giraffe's 

 neck as an illustration of the alternation of path. The saving in 

 nerve-fibre which the direct spinal route would afford in long-necked 

 mammals like the giraffe and camel seems to have been the deter- 

 mining cause for the abandonment of the long spinal-accessory route, 

 which would demand a nerve about double the length of the neck, 

 instead of one of a few inches, if the direct spinal path is adopted. 



That the diagnosis has been correct is now evident from the 

 fact that considerable wasting has occurred (May 18th) in the 



