444 TUMOURS. 



cancer, by injecting weak acetic acid into the tumour. Tho 

 suggestion has arisen from the fact that acetic acid destroys 

 the cells of cancer, transforming them into amorphous matter. 



SOFT CANCEK. 



Tliis is met with in two forms, namely, medullary sarcoma 

 or cerebriform tumour, and the colloid, alveolar, or gelatini- 

 form, as it is variously named. The term colloid seems to be 

 preferred by modern writers. 



(1.) Colloid Cancer. — I have met with specimens of colloid 

 cancer, since the publication of the first edition of this work, in 

 the ovaries, kidneys, and in the brachial lymphatics. The 

 specimens, as well as one met with in the duodenum of the 

 horse by Br. Young, were found to correspond with those seen 

 in human beings, in whom it is found as a jirimary disease, 

 principally in the digestive organs, uterus, mammary gland, and 

 peritoneum : and, as a secondary disease, in the lungs and 

 lymphatic glands. It consists of fibres so arranged as to form 

 alveoli or spaces, varying in size, and containing a soft, viscous^ 

 and nearly liquid matter, grey or amber-like in colour, but 

 sometimes opaque, and of a greenish yellow hue. This is the 

 true colloid, or glue-like substance. The density of the tumour 

 will depend upon the proportions of its two constituent 

 materials. If the colloid matter predominates over the fibrous 

 material, the tumour will have a soft, fluctuating feel, and will 

 be made up of large masses of colloid substance, intersected by 

 white fibrous cords or thin partitions, arranged as in areolar 

 tissue. But when the fibrous texture is predominant, the 

 tumour will appear as a tough, white, fascia-like mass, con- 

 taining small separate cavities or cysts filled with the colloid 

 substance. 



(2.) Medullary cancer is developed in the form of circum- 

 scribed tumours or infiltrations. The case from which the 

 specimen seen in Photo-lithograph, Plate IV., Fig. 4, was taken,^ 

 presented both varieties, the circumscribed, as well as the in- 

 filtrated form, in the mammary region ; infiltrations only in the 

 submaxillary space, and one well-defined circumscribed tumour 

 (that represented in the figure), weighing four pounds, upon the 

 outer side of the thigh. 



