DISEASES OF THE TAIL. 757 



iodine and administration of potassium iodide is generally preferable. 

 Tumours near the end of the tail are dealt with by docking ; those 

 near the base are, however, more serious, and necessitate amputation, 

 a double-flap operation being that generally employed. 



Bayer proceeds as follows : After shaving and disinfecting the 

 skin, a rubber cord is tightly applied round the base of the tail. Two 

 flaps are then formed by semi-elliptical incisions of suitable length 

 so as to ensure sufficient skin being left to cover the stump without 

 tension. The tail is then divided close to the base of the flaps, by 

 disarticulating one of the caudal joints. The rubber cord is then 

 cautiously relaxed, any bleeding vessels are picked up and ligatured, 

 the wound is thoroughly cleansed, and the two flaps are carefully 

 brought into contact. When the initial incisions have been 

 skilfully made, the flaps will cover the stump without difficulty, 

 and without being either tightly stretched or inclosing too large 

 a cavity. It is best to form the flaps rather longer than absolutely 

 necessary in the first instance, as they can afterwards be easily 

 reduced with scissors or the knife. The edges are then brought into 

 exact contact with closely inserted silk sutures, and should any 

 cavity remain a couple of " tension sutures " are used to obliterate 

 it. The several stages of the operation are well shown in the fore- 

 going illustrations (Figs. 453 to 456). 



X.— NECROSIS OF THE LUMBO-DORSAL FASCIA. 



The lumbo-dorsal fascia (fascia lumbo-dorsalis) lies beneath the 

 panniculus in the region of the back, and covers the dorsal extensors like 

 a sheath. Its superficial portion arises from the outer angle of the ilium, 

 becomes attached to the superior spinous processes of the lumbar and 

 dorsal vertebrae and to the ligamentum nuchse, and continued downward 

 in the fasciae of the abdominal muscles, and forward to the scapular fascia. 

 Its deep portion is confined to the lumbar region. It connects the trans- 

 verse processes of the lumbar vertebrae to one another and to the outer 

 angle of the ilium. The dorsal fascia gives attachment to various 

 muscles, and forms the medium of connection between the extensors of 

 the back and the muscles of the hind- quarter. It is best developed in 

 horses. 



Suppuration in the skin of the back following external injury 

 with infection, sometimes results in necrosis of the dorsal fascia. 

 Sooner or later large tracts are destroyed. Moller has repeatedly 

 seen this in horses ; cases last for weeks, and give the greatest 

 difficulty in treatment. Recovery is quickest after surgical removal 

 of the diseased portion ; pus formation is checked by continuous 



