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umbelliferous plants,, and the meadow-sweet bave all been found 
affected. 
The species found on grasses, especially the cocksfoot, has 
been already alluded to. The conceptacles contain from twenty 
to twenty-four ovate sporangia, each enclosing eight spores. 
The appendages and mycelium are much interwoven. 
Another of these “ white mildews/'’ not only on account of 
its frequency of occurrence on certain plants, but also from 
the numerous species of phanerogamous plants on which it is 
found (fig. 25), maybe truly designated “common” (Erysiphe 
communis , Lk.) ; many kinds of crowfoot, especially Ranun- 
culus acrisj are subject to its parasitism. It is found also on 
other plants of the same natural order, on the rest-harrow, 
trefoils, enchanters nightshade, bindweed, and knotgrass. 
There are from four to eight sporangia in each conceptacle con- 
taining from four to eight spores (fig. 26). In this species, 
more especially, M. Tulasne found curious sucker-like pro- 
cesses developed on the threads of the mycelium (fig. 27) ; their 
office may probably be only that of attachment. 
Of the other species found in Britain an enumeration will 
suffice, since they contain no feature of interest to the micro- 
scopist ; and all the members of this section are far less beau- 
tiful than those in other genera (especially Micro sphceria ) . 
The leaves of the dogwood or cornel are the home of one 
species ( E . tortilis , Lk.), and the burdock of another (E. 
Montagnei , Lev.) ; both of these in addition to the above have 
sporangia which contain more than two spores. There are 
also two species in which only two spores are contained in 
each sporangium. One of these (E. Linkii , Lev.) is found on 
both surfaces of the leaves of the mugwort ; the other ( E . lam - 
procarpa , Lev.) occurs on salsify, scorzonera, weasel-snout, 
and plantain. 
These complete the Erysiphei , but there are allied species of 
too much interest not to be noticed in connection with them. 
Before doing this we will, for the benefit of the botanical 
microscopist, append a brief view of the characters of the 
groups already reviewed. 
Conceptacle with one Sporangium — 
Appendages floccose ... ... ... Spluerothcca. 
Conceptacle with many Sporangia — 
Appendages needle-shaped 
Appendages hooked 
Appendages dichotomous 
Appendages floccose 
Phylladinia. 
Uncinula . 
Microsphceria. 
Erysiphe. 
Three very singular fungi are found on damp straw and 
paper, two on the former and one on the latter. Of the 
