170 ENCHONDROMATA. 



jelly-like; the fluid which oozes from its cut surface contains 

 mucin ; so that we are compelled to acknowledge the myxomatous 

 cliaracter of the growth, and to call it (should the entire tumour 

 have undergone this degenerative change) no longer a lipoma, 

 but a myxoma. 



Lipomata, in common with fibromata, are very justly regarded 

 as decidedly benign. A lipoma, once thoroughly extirpated, 

 never recurs ; metastases to neighbouring lymphatic glands or 

 to internal organs have never been observed. 



c. Encliondromata or Cartilage Tumours. 



§ 135. The term enchondroma is applied to cartilage when it 

 appears in the form of a tumour at some point in the body where 

 no cartilage should normally exist. The substance of an enchon- 

 droma therefore presents the peculiar elastic hardness, and the 

 milk-white colour, translucent in thin layers, which are char- 

 acteristic of cartilacre. As reo;ards minute structure, normal 

 histology, as everybody knows, distinguishes between, se^'eral 

 varieties of cartilage ; and particularly between hr/alhie cxirtilagcj 

 Avhose matrix is homogeneous, and fihro-cartUage, whose matrix 

 is fibrous. But the cornea also yields chondrin on boiling, and 

 its tissue may very w^ell be regarded as a form of cartilage, whose 

 cell-containing cavities are stellate, with branching processes 

 {cartilage ioith stellate cells). 



All these textures may coexist in an enchondroma, yet 

 hyaline cartilage as a rule predominates. One of the most 

 characteristic and most frequent combinations is that of small 

 rounded islets of hyaline cartilage passing at their periphery into 

 fibro-cartilage or corneal tissue. The hyaline cartilage forming 

 the nucleus of each islet differs in no respect from the well- 

 known physiological type. The cells are either single, or arranged 

 in pairs or groups, showing how the limits of each primary 

 element have been extended by subsequent endogenous proli- 

 feration. The capsules are not always distinct; their entire 

 absence is a sioui that the matrix is bemnnino; to soften. The 

 protoplasm of the cells is of variable form. It is usually stellate, 

 and contains a nucleus ; this form may either be due to shrinking 

 of the cells under the influence of reagents, or to the spontaneous 

 contractility of the protoplasm ; the latter explanation being 



