REPRODUCTION OF THE A8COMYCETES. 
35 
Perhaps it would be better, for the distinction of the two orders 
of spores, laying on one side or not their mode of development, to 
address oneself to known characteristics deduced from the nature of 
the envelopes and their number. 
In the superior Fyrenowycetes, where the variation of the forms 
extends through very narrow limits, the insertion of the spermatia, 
that is to say, their birth, upon some more or less elongated branches, 
upon short sessile sterigmates upon the division, may be of some 
importance ; but among certain less elevated Ascomycetes, where 
the variation is excessive, this consideration evidently loses some 
of its importance. While preserving it as a general indication, 
can we not obtain some better result from a criterion borrowed from 
the other order of ideas ? We should give, then, a greater im- 
portance to the constitution of the spore itself : the spermatia are 
spores with slim partitions born upon the joints of particular 
branches ; the stylospores appear to be in general spores with a 
double envelope. The first passes an extensible, dilatable mem- 
brane ; the latter, clothed with an external membrane, dilatable 
also in a certain measure, must break through it in order to de- 
velop: their organisation is more complete. They are alsoacroge- 
nous spores, but they are not conidia of the same order as the 
others : they are Chlcmydea conidia. 
We have seen in the preceding pages that, like the stylospores, 
the spermatia are endowed with a germinative property ; the great 
resemblance of these last to certain conidia permits us to ask 
what is the definition of the spores which M. Tulasne designates 
under the name of conidia ? This definition is contained in the 
fact that they are born perfectly freely at the surface of the Asco- 
mycete, and not contained in any special cavities. But, in exa- 
mining the series of the species presenting conidia, we see that there 
are some very different kinds : some small, with a slight mem- 
brane (Xylaria), the others large, with a thick membrane(^ilf<?- 
lanconis) ; it is then necessary to demand if, under this name of 
conidia, the first may not be the analogies of spermatia, the second 
of stylospores, and if under this appellation one does not confound 
the two orders of organs. In place of three orders of non-com- 
parable spores, there will not be remaining more than two ; this 
will be a great simplification in the study of the reproductive forms. 
In order for us to be quite clear upon the exactitude of this 
conception, let us search, by the way, some stylospores and sper- 
matia, still sufficiently clear of certain species, and recall those of 
the superior Pyrenomycetes, with the more variable and polymor- 
phous organs of the inferior Ascomycetes, and there shall we find 
ourselves led to consider some forms of Mucedines. 
We must not conceal from ourselves that, between the one and 
the other, there are some solutions of continuity, and that in some 
cases the analogy will, perhaps, be remote at first sight ; this is the 
natural consequence of the facts themselves. It will, perhaps, be 
possible moreover, to fill up later on the more considerable gaps. 
