152 



and at 15 cm. from its end was encircled by a distinct haemorrhagic 

 demarcation. On section the musculi coccygei showed pronounced 

 atrophy of the fasicules of muscles, sero-fibrinous imbibition of the intra- 

 muscular tissue, and in a few places shght superficial suppuration. The 

 vertebrae and the intervertebral cartilages are intact, a shght separation 

 of the periost is only remarked in two places directly under intramuscular 

 abscesses. Towards the base of the tail the lesions become gradually less 

 pronounced and the course of the affection along the lymph vessels of 

 the subcutaneous and intermuscular tissues is evident. The lymph gland 

 weighs 22-2 grams, its capsule is shghtly haemorrhagic, infiltrated, and 

 thickened. A large quantity of fluid flows on section, the gland is other- 

 wise absolutely normal in appearance with exception of the dark red 

 infiltrated marginal sinus. 



Microscopical Lesions of the Subcutaneous Tissues. 



Specimens taken from cases 1 and 3 serve as a basis for my investi- 

 gations on the lesions in the dewlap ; cases 5 and 7 for those in the 

 caudal apex. It is a notable fact that although the skin of the dewlap 

 is hardly thickened, measuring 8-5 mm., it measures often over 1 cm. on 

 the tail, which would normally be less than that of the dewlap. Bacteria 

 can be demonstrated, the cracks and ruptures due to the oedema gave 

 them access and a suitable substratum to multiply on, facihtating the 

 formation of abscesses. 



As far as it is present the stratum, corneum presents advanced 

 desquamation and flask-shaped masses in a fibrous tissue rich in leuco- 

 cytes. These masses consist of necrotic detritus, and lie in small holes 

 in the epidermis close to the stratum lucidum. Dense small celled foci 

 of infiltration and young deeply staining tissues separate them from the 

 intact cells of the stratum lucidum. The infiltration increases in pro- 

 portion to the suppuration. In places the whole of the corium, together 

 with the epidermis, is necrotic ; only a few stainable nuclei are seen in 

 the innermost layers of the stratum reticular e, surrounded by karyo lytic 

 and plasmolytic elements. Externally this layer is covered by a stratum 

 of faiatly staining fibrine. Where the pleuro-pneumonia virus has acted 

 solely on the deeper layers, and the pressure caused by the oedema has 

 left the surface of the skin undamaged, the stratum basale contains a few 

 foci of leucocytes, as sign of a coming infiammation. 



The corpora fapillares are full of emigrants, the blood vessels dis- 

 tended, a few lymph spaces are remarkable on account of their great size 

 and coagulated contents, employing fibrine staining. The lesions become 

 more peculiar, but also more famihar in the deeper layers of the sub- 

 cutaneous tissue where the folhcles of hairs become more frequent. Darkly 

 staining margins of leucocytes surround the capillaries, whose walls are 

 almost always slightly thickened ; between these emigrants, and closely 

 attached to them, is a fine reticulation of fibrine. The single fibres of 



