487 
In the case of leaves the negative may be secured from the 
freshly gathered specimens without any preparation; but dry ob- 
jects from the herbarium work fully as well and often better when 
they are first saturated with the kerosene, in the same way as for 
the negative sun-prints and wiped free of excess of oil before 
being placed in the frame. 
It was my hope to show to the readers of the BULLETIN actual 
specimens of the work done by the Solandi process, but it may 
be even better to present two engravings, as they will indicate 
that the sun prints may be used for illustrations in printed articles 
with a fair degree of success. Figure 1 shows a leaf of the com- 
Fic. 1.—HoLtityHock LEAF WITH Rust (Puccinia malvacearum, Mont.). 
mon hollyhock badly infested with the rust (Puccinia malvacearum, 
Mont.); this object being chosen as one that is a fair average as 
pathological specimens go, there being no marked light and dark 
patches as seen from a surface view. The transmitted light brings 
out the sori of the Puccinia in sufficient prominence to make them 
fairly distinct and much better than could have been done by or- 
dinary photography. The second is another leaf (Polygonatum), 
