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The hyphz forming the podetium rise from the gonidial layer 
of the thallus, branches grow from the latter upright or at right 
angles in little tufts, till they break through the rind. These he 
calls fruit primordials, and they often carry up with them in their 
growth some of the gonidia of the layer from which they 
started. Before the primordials have broken through the surface, 
the ascus bearing hyphe may arise. It is not possible in all 
cases to distinguish exactly where a cell ceases to be an ordinary 
hypha and becomes an ascus. Certain cells increase in diameter, 
and as one follows them upward, they are seen to end in ascus 
cells or asci. In some cases it was certain that these ascus 
branches originated from the primordial or sterile branches. 
He divides the whole genus in two classes, according to the 
relative time of the differentiation of the fruit hyphz from the 
sterile ones, or perhaps more correctly, the time of the origin of 
the fruit hyphe. When they originate early in the life of the 
fruit body, then the latter is inclined to remain more or less sim- 
ple in form, so in this class are placed all having simply formed 
podetia. In the second class are all the cup, funnel, and variously 
branching forms. It is in thislatter class that the polymorphism be- 
fore referred to reaches its highest development. The podetium, he 
claims, has the same morphological significance as the fruit-body 
of the ordinary fungus. In the latter group of plants this organ 
is so uniform in shape in related species, that it is made the ground 
of classification. Here is the single genus C/adonia, it varies in 
shape from a small conical projection, through a series of different 
forms till it reaches a structure like that of a well branched tree. 
The causes of this branching are very carefully traced, so far as 
they may be considered of purely mechanical origin, such as un- 
equal tensions coming from various causes. In connection with 
this comes what is termed various grades of sterility of the fruit- 
body. Of course, this expression can only be used on the 
assumption that the podetium is a fruit-body and not a thallus. 
It is well known that many of these bodies produce no spores, 
and in reference to this the author says, all grades of sterility may_ 
be found, from the extreme, where there is no differentiation of 
sterile and fertile threads, that is where the fruit primordials 
compose the whole podetium, from this extreme up to that where 
