ENCHONDROMATA. 171 



especially applicable when a conversion of the hyaline cartilao-e 

 into mucous tissue is taking place. Under such circumstances, 

 the formation of processes coincides with the disappearance of the 

 capsules, and a mucous intumescence of the matrix. Virchow 

 has observed cells with processes of colossal length in an enchon- 

 droma undergoing this change (^Virclioius Archiv, 28, p. 238). 

 Towards the periphery of these islets of cartilage, the cells 

 decrease in size, they become flat and lenticular ; the matrix 

 shows stria?, and is traversed by fibres of variable thickness, 

 which resemble elastic fibres and are remarkable for their stifi- 

 ness {jihro-cartilagc). Or else the cells may become spindle- 

 shaped and stellate, they may anastomose with one another, and 

 be obviously situated in a lacunar system provided with nodal 

 points, while the intercellular substance retains its homogeneous- 

 and transparent quality {cartilage unth stellate cells, corneal tissue). 

 Neighbouring islets of cartilage are in contact by these outer- 

 most zones of fibro-cartilage or cartilage wdth stellate cells, and 

 are thereby united into groups, forming nodules or lobules as 

 large as a pea, of which the entire tumour appears to the naked 

 eye to be made up. 



§ 13G. The above sketch of the microscopical appearances 

 shows that enchondromata are also endowed with a lobulated 

 structure ; but their lobulation differs very essentially from that 

 of a lipoma, or even from that of a papilloma. The lobules of an 

 enchondroma are co-ordinate with one another ; they have grown 

 up side by side ; it is only this topographical juxtaposition of the 

 lobules, and not any higher unity, such as a common vascular 

 apparatus, or a growth b}- development ah intra, which unites 

 them into a single whole. Although it is noteworthy, as seeming 

 to point to an organic type of structure, that the individual 

 lobules of which an enchondroma is made up, never exceed a 

 certain size, yet this is explained by the simple fact, that cartilage 

 generally — even in the normal course of development — is not 

 deposited in continuous masses of large size, and — to use a teleo- 

 logical form of expression — ought not to be so deposited. Cartilage 

 being a non-vascular tissue, is nourished by the transmission of 

 nutrient fluid from cell to cell. At a certain distance from the 

 vessels which carry the blood, this mode of nutrition becomes 

 impossible ; and unless some now arrangement be provided for 

 the supply of the central parts, disturbances of nutrition in thoso 



