STRUCTURE. 57 
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 infiuence of the rapid growth of these organs, 
it soon produces at its summit a fissure of the external mem- 
brane, which becomes a more marked depression in the mar- 
ginate 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. 
The receptacle proper comprehends the subhymenial tissue, 
the parenchyma, and the external membrane. The subhymenial 
Fia. 33.—Section of cup of Ascobolus. u. External cells. 6. Secondary layer. c. Sub- 
hymenial tissue (Janczenski). 
tissue is comyosed 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 to- 
gether, and sometimes separable. Externally it is sometimes 
smooth, and sometimes granular or hairy. 
x ? , 
