rrive at a general idea of the structure in the cupulate
Discomycetes. They present themselves at first under the form of a
small rounded globule, and almost entirely cellular. This small
globule, the commencement of the receptacle, is not long in increasing,
preserving its rounded form up to the development of the asci. At this
period, under the influence of the rapid growth of these organs, it soon
produces at its summit a fissure of the external membrane, which
becomes a more marked depression in the marginate species. The
receptacle thus formed increases rapidly, becomes plane, more convex,
or more or less undulated at the margin, if at all of large size.
Fixed to the place where it is generated by some more or less
abundant mycelioid filaments, the receptacle becomes somewhat
cup-shaped and either stipitate or sessile, composed of the
receptacle proper and the hymenium.

[Illustration: FIG. 33.--Section of cup of _Ascobolus_. _a._ External
cells. _b._ Secondary layer. _c._ Subhymenial tissue (Janczenski).]

The receptacle proper comprehends the subhymenial tissue, the
parenchyma, and the external membrane. The subhymenial tissue is
composed of small compact cells, forming generally a more coloured and
dense stratum, the superior cells of which give rise to the asci and
paraphyses. The parenchyma is seated beneath this, and is generally of
interlaced filaments, of a looser consistency than the preceding,
united by intermediate cellules. The external membrane, which
envelopes the parenchyma, and limits the hymenium, differs from the
preceding by the cells often being polyhedric, sometimes transverse,
and united together, and sometimes separable. Externally it is
sometimes smooth, and sometimes granular or hairy.

The hymenium is, however, the most, important part, consisting of (1)
the paraphyses, (2) the asci, and sometimes (3) an investing mucilage.
The asci are always present, the paraphyses are sometimes rare, and
the mucilage in many cases seems to be entirely wanting.

The paraphyses, which are formed at the first commencement of the
receptacle, are at first very short, but soon elongate, and become
wholly developed before the appearance of the asci. They are linear,
sometimes branched and sometimes simple, often more or less thickened
at their tips; almost always they contain within them some oleaginous
granules, either coloured or colourless. Their special function seems
still somewhat obscure, and Boudie