ROUND-CELL SARCOMATA. 14) 



a cell, we are obliged to have recourse to liartlcning the tumour 

 and staining it with carmine.* 



The structure of a round-cell sarcoma differs from that of 

 ordinary granulations only in degree. Some of the vessels are 

 wider and have thicker walls ; but where they break uj) into 

 ca})illaries, they are quite as frail as those of gramdation-tissucj 

 consisting frequently of no more than a single layer of cells. 

 Their interstices are uniformly packed with the round-cells, and 

 the scanty, soft, amorphous matrix of the embryonic tissue. Ju 

 rare cases, the entire tumour is more highly diti'erentiated ; it 

 recalls the papillose variety of granulations, exhibiting radiating 

 stride, along which it has a tendency to split up. On a subsc- 

 (|uent op})ortunity we will say more about these fasciculated 

 round-cell sarcomata which spring by ])refercnce from the i)erl- 

 osteum, where they are known under the name of Mirconia 



The simple round-cell sarcomata originate most connnonly 

 from membranous ex[)ansi()ns of connective tissue ; they grow 

 by 2)reference from the })erIosteum and the membranous invest- 

 ments of the nervous centres ; we nuist however be jn'eparcd 

 occasionally to recognise them in other ])arts as well, in the skin, 

 the mucous and serous membranes, nay even in the glands. The 

 simple round-cell sarcoma is closely related to the small-celled 

 spindle-cell sarcoma, and thro'iHi this to the fibroma; it often 

 passes continuously into these toims. In harmony with this is 

 the comparative benignity which distinguishes this variety among 

 all other round-cell sarconuita. 



§ 12"). II. — 77/6' lij)iipluide)iOLd roHiid-cell sarcoma (sarcoma 

 lymphadenoides, molle). This variety owes its softer texture 

 mainly to the circumstance that its cellular elements are less 

 closely aggregated than thoseofordinar}- granulation-tissue. On 

 scrajnng its cut surface a juice, loaded with cells, is readily 

 obtained ; on microscopical examination these prove to be round- 



* Vircliow is incUiied to ascribe the ai)pcavance of the seemingly free 

 nuclei to an excessive frailty of the bodies of the cells ; and he takes the 

 opportunity of adding an observation whicli all practical histologists 

 should lay to heart (On Tumours, y. *20-l) ; '* this frailty of the cells is so 

 .striking, that 1 have long been in the habit, -whenever a recent tumour 

 t^ecms to consist mainly of largo, naked nuclei, with large, lustrous 

 nucleoli, of at once suspecting that I liave to do with a sarcoma." 



