NOTES AVD MEMORANDA. 287 



As the haematoxylin shows the presence in the silver pre- 

 parations of cell-nuclei corresponding]^ to the whole spaces, 

 so the treatment with gold shows that these nuclei correspond 

 to protoplasmic hodies which — the conclusion will hardly he 

 assailed — correspond, on the whole, to the spaces in the silver 

 preparations. It is quite another question whether these 

 masses of protoplasm completely fill the spaces or not. Proof 

 of this could only be obtained were it possible to produce 

 both the gold and the silver appearances in the same pre- 

 parations. As is well known, however, if a preparation be 

 treated first with silver, then with gold, the effect is only to 

 produce a reduction of the latter in the parts impregnated 

 with silver, whilst the converse mode of treatment altogether 

 fails to yield the silver spaces. The question must, there- 

 fore, so far remain unsettled. All one can say is, that on 

 both silver and gold preparations appearances are frequently 

 obtained which, as regards form, are precisely similar, appa- 

 rently even to the minutest details, although it is not every- 

 where possible to trace the same exact resemblance ; for 

 instance, the protoplasmic masses of the one might be said 

 to be smaller relatively than the spaces of the other ; the 

 sizes, however, in both are so varied that it is difficult to 

 compare them. If the forms obtained by the gold treatment 

 differ from those obtained by the silver treatment, in one 

 point more than in another, it is in the diameter of the pro- 

 cesses, which here and there appear somewhat smaller and 

 more tapering than those proceeding from the spaces of the 

 silver prepararion. On the other hand, the appearances pre- 

 sented in silver preparations which have been placed in 

 spirit are in favour of the idea that the spaces are completely 

 filled by protoplasm. In these it occurs here and there, 

 although it must be admitted, not generally, that both 

 nucleus and protoplasm may be made out, the latter appear- 

 ing as a finely granular substance, which is separated from 

 the brown intercellular substance by a crescentic clear zone 

 or space (perhaps caused by a shrinking of the protoplasm). 

 We may conclude, therefore, that the white spaces and canali- 

 culi shown to exist in the synovial membrane by treat- 

 ment with nitrate of silver, correspond generally to a proto- 

 plasmic network (made evident by chloride of gold), 

 consisting of connective-tissue-corpuscles. 



A similar statement may be made with regard to the car- 

 tilage-cells of the surface, which appear after treatment with 

 silver as round white spaces, in which haematoxylin brings 

 the nuclei into view; whilst, on the other hand, chloride of 

 gold colours the protoplasjn of the cells. 



