392 INFLAMMATION. 



ersed by numerous very fine threads, which are cone-shaped. Their bases 

 are directed toward the nucleus, from the periphery of which they arise, while 

 their points are in connection with the nearest granules of the protoplasm. 

 Within the corpuscle there are finer and coarser granules, all being connected 

 with each other by very fine threads. The seam around the nucleus, as well 

 as the spaces between the meshes of the threads, are observable, being much 

 lighter than the latter. 



From the periphery of the bioplasson body numerous thick offshoots enter 

 the larger canaliculi, which sometimes can be followed up until they commu- 

 nicate with the bioplasson of other large neighboring canaliculi. Besides 

 these, many very fine offshoots run from the periphery of the bioplasson, con- 

 tained in the larger canaliculi towards the basis-substance. Some of them 

 can be seen to enter the fine canaliculi, but their course cannot be distinctly fol- 

 lowed. My preparations show a much finer net-work within the basis-substance 

 than Heitzmann's figure, before alluded to. Though I am not able to distinctly 

 demonstrate the presence of living matter in the finest canaliculi, yet, as we 

 find it in all other kinds of connective tissue, I am justified in assuming it. In 

 normal bone, the lacunae and canaliculi are not entirely filled by the living mat- 

 ter. On the periphery of each corpuscle we see a distinct light seam, traversed 

 by the offshoots, which, in a cross section, only show the bioplasson in the center 

 of the canaliculis, hence leaving sufficient space for the nutrient circulation. 



It is impossible to study the differences between necrotic and normal 

 bone if the specimens be prepared from dry osseous tissue. 



I have made microscopical' examinations of necrotic bone from the lower 

 Jaw, and from another piece from an upper jaw removed by Dr. Frank Abbott. 

 The methods employed were exactly the same as before described from nor- 

 mal bone. In both cases the necrotic sequestra, as soon as they had been 

 taken from the mouth, were placed into the solution of chromic acid, and cut 

 in due time. As these pieces were small, I imbedded them in a mixture of 

 paraffine and wax (after the extraction of the water by treatment with alcohol 

 for twenty-four hours), whereby I was enabled to obtain extremely thin sec- 

 tions, some of which I stained with chloride of gold, some with haematoxylon, 

 and some I mounted unstained. 



The results of these examinations were as follows : 



The outer surface of the necrotic bone, which, to the naked eye, looked 

 rough and eaten out, when brought under the microscope showed bay-like 

 excavations, known formerly as " Howship's lacunce," in which there was 

 visible a granular mass mixed with pus-corpuscles. In the middle of the bone 

 I found all the Haversian canals more or less enlarged, some showing the bay- 

 like excavations. The contents of the Haversian canals were everywhere the 

 same a conglomerate mass of darkly shaded granules, which I was unable 

 to stain with carmine. These masses are the same that we see in decomposi- 

 tion of organic matter "micrococci." Here and there some medullary cor- 

 puscles and multinuclear bodies were recognizable. I did not see blood-vessels 

 in any of the Haversian canals. In the necrotic bone I found the traces of 

 former osteitis. The enlargement of the Haversian canals and lacunae are 

 direct proofs of this ; the dissolving out of the basis-substance "on the per- 

 iphery may, on the contrary, have been due to chemical changes, produced by 

 infiltrations from the neighboring inflamed tissues. The Haversian systems 

 and concentric lamellae were unchanged. The lacunae and canaliculi were yet 

 preserved. In the necrotic preparation from the lower jaw I observed many 



