58 REPORT OF THE BOTANIST. 
The spores germinate readily in water and produce germ tubes 
from either one or both cells, from any point of the cell wall. 
The hyphz or germ tubes probably gain access to the interior of 
the rusted carnation leaf through a stomate. Once within and 
adjacent to the rust hyphe, the parasitism begins and the two 
plants become closely interwoven. The growth of Darluca is 
most abundant close to the pustules of the rust. The leaf tissue’ 
beneath the infested spot seems filled with the hyphe of the two 
fungi. Often a dark layer is developed at the original surface of 
the leaf, above which rise the spores and the pycnidia of the two 
fungi. The dark color may not be confined to a mere layer or 
band, but may-extend to the whole of the dense mass of hyphz, 
almost totally obscuring the structure of the carnation leaf. 
The pycnidia are imbedded for two-thirds of their height 
among the spores of the rust, showing only the dark upper third 
when seen from above. The surface is smooth and rather shiny, 
and is marked with a fine irregular network of cells. At matur- 
ity an opening is formed at the apex through which the spores 
exude when wet. In the specimen figured (Plate III, fig. 8) a 
thousand spores were visible, and more were constantly issuing 
from the pycnidium at the left. 
The same fungus infests the rust of the asparagus; and it may 
be that, either by growing garden asparagus in the houses or by 
spraying the carnations with water in which Darluca infested 
~ asparagus has been broken a sufficient abundance of Darluca 
may be obtained to check the ravages of the-rust. 
At the present writing it is not known to what extent rust may 
be checked by the Darluca. It can not be expected to eradicate 
rust from a greenhouse, but its influence is good and it is believed 
to be worth the florist’s while to encourage its growth. 
