596 
MR, H. M. WARD ON THE MORPHOLOGY AND THE 
In the typical simpler Erysiphece, such as Poclosphaera, as is well known from De 
Bary's classical researches,* the “carpogonium” and “antheridium” arise each as a short 
lateral branch from separate hyphse, at the point where two hyphae cross : each becomes 
cut off by a septum, which is formed close to the parent hypha in the case of the pyri¬ 
form “ carpogonium,” and about half way up the curved “ antheridium ” branch. The 
free end of the latter becomes closely applied to the top of the carpogonium , and 
fertilisation—possibly not complete in a physiological sense, however—is said to be 
complete. After this process numerous branchlets arise from the base of the anthe¬ 
ridium filament (and also from the base of the carpogonium), grow rapidly and with 
numerous segments, and invest the carpogonium,, which meanwhile begins to be (more 
slowly) cut up into cells. 
In Eurotium f we have an essentially similar process, except in minute details, and 
the antheridium is a branch springing from the same hypha which bears the carpo¬ 
gonium, and arises just beneath the latter. Here, as before, the perithecium envelope 
is formed chiefly by the rapid overgrowth of cells derived from the antheridium branch. 
It is quite conceivable that a form allied to Erysiphe and Eurotium, &c., might have 
the unicellular carpogonium and antheridium arising quite in contact at their bases 
from the same branch. 
If we now compare the above with the succession of events in the development 
of Meliola, the following points of analogy seem to me sound. The original pyriform 
branchlet—containing in itself, so to speak, the elements of the fruit-body—after the 
first division (Plate 42, fig. 9), may be considered as establishing morphologically an 
“ archecarpium ”1 and an antheridial branch —or the latter may be considered as 
containing in itself the antheridium, plus the elements of the perithecium wall. 
If the cells A and B (fig. 9) became further developed, and diverged at their apices, 
we should have no difficulty in seeing these points of homology. 
Thus much cannot but be allowed. The cell A resembles a true archecarpium in so far 
that it slowly produces the ascogonium and asci; the homology will not be weakened, 
but the contrary, if further research shows that part of the perithecium wall results from 
cells derived from A. The cell B so far acts as an antheridium branch in that it is 
closely applied to A, divides up more rapidly, and thus produces most —perhaps all — 
of the perithecium wall. 
The above may possibly suggest some difficulties to those who have not followed the 
recent progress in our knowledge of sexual organs and their homologies in the lower 
fungi. It has of late been showm to be not improbable, but on the contrary very 
likely 7 , that we should view the Erysipliece as a group connecting the higher Ascomy- 
* “ Beitr. z. Morph, u. Pliys. d. Pilze,” R. iii., 1870. 
f Gf. De Bap.t, loc. cit. 
X De Baby, Beitrage IV., proposes to use this word as denoting that part of the body which becomes 
the ascus and pedicel in Podosphaera, 
