122 On the Morbid Growths from a case of 



1st. The consistence of this mass varies considerably ; the 

 greater part immediately surrounding the bone is very hard, whilst 

 the external portions are soft, the density increasing from without 

 inwards. The matrix of the dense portions consists of large 

 irregular fibres varying in size from y^Vir to ^^V?7 of an inch in 

 diameter, arranged in parallel bundles, radiating from the surface 

 of the femur to the periphery of the tumour, but also presenting in 

 some parts a dense irregular network, due to those radiating fibres 

 crossing each other and uniting at various angles ; each of these 

 fibres gives off at irregular intervals branches, which radiate in 

 various directions and join other fibres and their branches. The 

 elements of the matrix in the central portions are so closely im- 

 pacted that few interspaces can be discerned ; but proceeding from 

 this position to the circumference the fibres become more and more 

 separated, so that they form large irregular alveoli varying in size, 

 in which the cell elements are enclosed. In the softer parts of the 

 tumour, more especially at the periphery, the bundles of large fibres 

 are separated by wide intervals ; the large spaces thus formed are 

 filled by masses of the softer elements. Externally the tumour is 

 covered by a dense layer of connective tissue, from which processes 

 representing trabeculae can be traced even into the dense central 

 calcareous parts ; but these processes are distinct from the fibres 

 proper of the matrix, and in no place are they observed united. 

 Tracing the fibres from without inwards, their structure is seen to 

 be — first, apparently homogeneous, then faintly fibrous, and finally, 

 calcareous ; but, although this is the predominant arrangement of 

 their structural peculiarities, yet all the blood-vessels are surrounded 

 by a zone of calcified fibres. No true lacunae nor canaliculi are to 

 be seen, objectives up to 4jj inch revealing nothing in the so-called 

 " osseous tissues," but minute calcareous granules and a few small 

 badly-formed cavities. The soft elements consist of spheroidal or 

 elongated oval cells, from ^irVu to ^-sVc of an inch in diameter, each 

 containing one or two well-defined nuclei. These cells are best 

 seen in the large alveoli situated in the peripheral portions of the 

 tumour ; advancing to the centre, the cells become gradually 

 smaller and more elongated, and are firmly attached to the fibres. 

 Tracing them still further, their nuclei only are to be seen, whilst 

 in the central calcified portions nothing approaching the character 

 of either cell or nucleus is visible : but the cells are scattered 

 throughout the calcareous zones surrounding the blood-vessels ; 

 closely attached to the wall, and projecting into the lumen of some 

 of the blood-vessels, are small collections of such cells. The large 

 peripheral spaces already described are filled with large masses of 

 cells in different stages of disintegration; some spaces contain 

 nothing but granular debris, in which minute oil-globules occupy 

 a prominent position, while in other sjDaces the cells are very 



