510 ON THE STRUCTURE OF SPHJERIA POCULA. 
whereas the microscope shows this to have been an error, the sup- 
posed ostiole being nothing more than pores, or openings in the 
disk, with no alteration of colour. By soaking in water for an 
hour or two my specimen became quite fleshy in its character, and 
sections were readily cut through the disk, so thin as to reveal the 
entire structure. This may be briefly described :—The pores 
which are visible on the surface penetrate the disk in parallel 
channels, at short distances apart, and are cylindrical, several 
times longer than broad, with no perithecia (as supposed by 
Schweinitz and Fries), but lined throughout with a layer of elon- 
gated elliptical cells, closely packed side by side, and in no way 
differing from the basidia which line the tubes of a Polyporus. 
In some instances these basidia were still crowned by delicate 
spicules, seen only when stained by aniline. The tubes contained 
numerous hyaline spherical spores, about ‘004 millim. diameter, 
and these seem to have been the cause of the white pulverulent 
appearance of the disk. Between the parallel tubes the substance 
was continuous, consisting of interlacing fibres proceeding from 
the base of the basidia inwards and downwards, in the direction 
of the stem. Hence the structure of the cup was a delicate 
fibrous tissue, perforated by parallel pores, opening in the disk; 
the whole internal surface of such pores being hymenial, lined 
with closely-packed basidia, originally having delicate spicules at 
their apices, bearing globose hyaline spores. 
Such a structure is undoubtedly Hymenomycetal, and no 
insinuation of Ascomycetal ; in fact, it is nothing else than the 
structure of Polyporus or Porothelium, with a preference for the 
former; and the species should in future be designated as Poly- 
porus (Mesopus) Pocula (Schwein.), allied perhaps in habit to 
Polyporus pendulus, but in substance to Polyporus Rhipidium. 
The objections to this view cannot be formidable, if the structure 
above described is accurate. The substance is no more fleshy than 
that of many Polyporei. The size is often scarcely exceeded in 
Polyporus Rhipidium, and hence dimensions would be no obstacle. 
The cup-shape is almost the same in Polyporus pendulus, although 
not so remarkably Pezizeform. In fact all the essential characters 
of Polyporus are present; and although shaped so much like a 
Peziza, we have the authority of Schweinitz for urging that the 
disk is not permanently and by preference exposed fo the light, 
as in Peziza and Poronia, but turned from the light, by the cups 
always becoming pendulous, as is the habit in Polyporus and 
other Hymenomycetes. 
