394 Dr. H. Charlton Bastian on the Origin 
remained for eight weeks, the turnip being in an atmosphere: 
saturated with formalin vapour. 
On examination this turnip was likewise found to be 
slightly shrivelled, and it was rather soft and doughy to the 
touch. On section the colour was almost natural, except for 
a depth of about one third of an inch round the periphery, 
where it was slightly discoloured, and in the centre, where 
there was a small area about one quarter of an inch in 
diameter which had a rather gelatinous appearance. 
Two sections through this central region and its neigh- 
bourhood were made, and then soaked in dilute ‘ mastzellen ” 
stain. On microscopical examination they were found to 
contain moderately large Bacteria, mostly in small groups, 
in a large number of the cells; though here and there larger 
masses of Bacteria were found, such as are shown in Pl. XXV. 
fig.6, B (x 500). In many of the cells the Bacteria seemed 
to be developing in and on the surface of the primordial 
utricle, and also in and on the surface of the nuclei of 
the cells. 
I have made only one experiment of this kind with an 
Apple, and in this case a rather small, but thoroughly sound, 
specimen was placed in a screw-top bottle, and stood on a 
small earthenware pot as before, so as to remove it from 
contact with some pure formalin which had been placed in 
the bottle. ‘The top was tightly screwed on, and the bottle 
was then placed in a cupboard, where it remained for eight 
weeks—the temperature of the cupboard varying during this 
time between 70° and 56°F. The apple was thus left, as the 
turnip had been, in an atmosphere saturated with formalin 
vapour *. 
On examination the surface of the apple was found to 
be hardened, and on section irregular patches of brownish 
discoloration were seen; otherwise nothing abnormal was 
observed. 
Microscopical examination of an unstained section showed, 
in a few of the cells, a small Fungus mycelium, such as may 
be seen in P]. XX VI. fig. 7, A (xX 250). Specimens like this 
were found in cells in different parts of the section, though in 
the great majority of them nothing of the kind was met with. 
* I have not had many successes with this method, and do not recom- 
mend it, especially as the soaking for a time in 10 per cent. formalin 
has proved to be pertectly sufficient to guard against external contami- 
nation. It is difficult to tell how far the formalin vapour penetrates into 
the substance of fruits or vegetables left in an sanoehae saturated with 
it for many weeks, 
a 
