APPENDIX B. xxv 



University College Hospital, had the opportunity of examining 

 some old crystals of ammonic tartrate (also prepared by the 

 same chemists) which must have been in the hospital-dis- 

 pensary for at least ten years. They were contained in a 

 small corked bottle, and many of them were slightly dis- 

 coloured having a somewhat dirty aspect. On solution in 

 a watch-glass most of these crystals yielded patches of fungus- 

 filaments and spores, bearing a very close resemblance to 

 those which had been previously seen. The quantity, how- 

 ever, was far larger than that met with in the more recent 

 crystals, and here the growths existed on the surface of 

 some of the crystals as well as in their interior. In these 

 patches, which had apparently grown through the crystal, the 

 filaments were also more developed. 



All the evidence, therefore, tends to show that growth 

 takes place within the crystal, and that the quantity of the 

 filaments and spores increases with the age of the saline 

 matter. 



Supposing, however, that the spores and filaments have 

 grown within the crystal, and that they are the developed 

 representatives of certain specks of living matter, two views 

 may still be taken as to the origin of such specks. Either ( i ) 

 they are some of the pre-existing 'germs' of the pansper- 

 matists, which have become mechanically enclosed within the 

 crystal, or (2) these specks of living matter have been evolved 

 therein by virtue of certain changes and re-arrangements 

 which have taken place amongst the not-living constituents 

 of the crystalline matter and the dead organic particles which 

 it encloses. 



Of these two alternative views I am, after reflection on the 

 following considerations and evidence, inclined to believe 

 that the latter is most probably the true one : 



(a). It must be remembered that however strange and un- 

 likely a situation the interior of a crystal may appear for the 



