PRINCIPLES OF VETERINARY SURGERY 555 



ered an enormous melanotic tumoi" on the cheek of a calf 

 six weeks old. Its histological nature was not determined. 

 In 1896, he cited the case of a calf afflicted with melanic in- 

 filtration of the cerebrum and cerebellum. Spots also ap- 

 peared in the mouth, cheeks, perilaryngeal region, oesopha- 

 gus, trachea, parietal pleura, and the investing membrane 

 of the thymus gland. There were also spots on the surface 

 and in the depths of the lungs, the heart, the liver and the 

 spleen. 



Dr. Fiorentini has seen numerous cases of melanosis in 

 the calf, most of which showed black spots on the lungs 

 with clear outlines. The spots penetrated to varied depths 

 into the parenchyma, and microscopic examinations proved 

 that the function of the lungs were not altered in the dis- 

 eased portions. In the connective tissue melanosis of the 

 calf assumes a special form. 



In the calf, the etiology is distinguished from that of the 

 ox. The nutritive anomaly of the subcutaneous connective 

 tissue manifests itself by deep spots of a black hue, which 

 a,re described under the name of "macular melanosis." 

 When skinned there are found in the under layer of the skin, 

 brilliant, black, clearly circumscribed spots two centimeters 

 in diameter, shaped like feathers, and giving the impression 

 that black feathers had been pasted under the skin. Only 

 the loose cellular tissue shows this coloring, and they can 

 be removed with forceps and deposited in a steel blade. 

 The microscope reveals fibrillary fasciculi, crossed with 

 voluminous fusiform cells of granular nature with color- 

 less nuclei. These cells are analogous to the lamina fusca 

 of the eye, ramified in stars and incurved. The entire con- 

 nective tissue is strewn with free melanic granules. 



This affection, is a congenital, heterotopic anomaly of 

 the mesodermic pigment, which disappears at a later period. 

 It has never been found in the adult bovidcc. According to 



