CHAPTER V.—COMPARATIVE REVIEW.—ASCOMPCETES. 241 
of the jelly, and which must necessarily be communicated to such small and light 
bodies. 
With these characteristics the spermatia cannot be certainly distinguished from 
small spores. The distinction however is, that, like those of Collema or Polystigma, 
they are all, as far as has been hitherto observed, zncapable of germination. 
Secondly, these organs all agree in having the spermatiophores collected together 
into close hymenia in the spermogonia. These spermogonia are usually, as in Collema 
and Polystigma, hollow receptacles like perithecia sunk in the tissue of the thallus, 
with the cavity smooth and pitcher-shaped, or, as is very often the case, repeatedly 
and very irregularly folded into sinuous depressions and projections, so that where the 
folds are narrow the receptacle has the appearance in section of being divided into a 

FIG. 114. Diatrype quercina, Fr. a a spermogonium on a piece of bark, laid open by removing 
the periderm. The conically pointed upper surface which is folded in coils bears the hymenium of 
the spermatia. 6 vertical itudinal section igh a sp jum; a tendril-like mass of sper- 
matia is issuing from an opening in the overlying periderm. cfragment of a thin section through 
‘the surface of the spermogonium with sickle-shaped spermatia and their sterigmata. After Tulasne. 
a and é slightly magnified, c magn. 360 times. 

number of compartments. The cavity is everywhere lined with the hymenium which pro- 
duces the spermatia, and the spermatia when mature are imbedded in jelly and occupy 
the centre of the cavity, and when the jelly swells in water they issue crowded together 
in drops or long strings from the narrow orifice of the spermogonium (Figs. 112, 113). 
Some Pyrenomycetes which live in the rind of trees form layers agreeing in 
every respect with the spermatiophores, except that they are not inclosed in receptacles 
altogether belonging to the Fungus; on the contrary they are disk-shaped or cushion- 
shaped bodies with the spermatiogenous surface folded into deep sinuous depressions, as 
in species of Diatrype (Fig. 114), Quaternaria, and Stictosphaeria, Tul., or else smooth 
as in Calosphaeria princeps, Tul., and in both cases covered only by the peripheral 
layers of the rind. The spermatia escape through a narrow fissure in the rind, 
[4] R 
