PYCNIDES OF CRUSTACEOUS LICHENS. 247 
sometimes slightly curved, occasionally having in their interior nuclei or granules. They 
are borne on short, simple, inconspicuous basidia. The cavity of the conceptacle is 
simple, its walls composed of brown cellular tissue. On the same trees, in the same 
locality, similar pyenides occur, scattered among the ordinary spermogones of L. albo- 
atra (corticola). Here, again, the question arises whether these bodies are to be regarded 
as a third form of reproductive organs, referable to the Lecidea, or whether they do not 
really belong to some other lichen or fungus. I know of no good ground for preferring 
the latter to the former supposition. 
Specimen 13. Var. eleochroma, Ach. On trees, Ballygomartin, near Belfast: Prof. 
Dickie, 1851. Spermogones are abundant, scattered about the black hypothalline 
boundary of the thallus, on both sides thereof. They are extremely minute black dots, 
which are scarcely visible even under the lens, unless when rendered turgid by moisture. 
They are rendered still more inconspicuous by the black shade that exists on either side 
of the hypothalline border. Spermatia are of the type, 4455 to rooy long when straight- 
ened out, seated on sterigmata also of the type. 
Specimen 14. Var. eleochroma. On the old bark of trees, Ardrum, near Cork, Mar. 
1858: Carroll. Spermogones are minute brown dots, scattered abundantly outside the 
region of the apothecia, irregular in size and form, semipellucid when moistened, and 
then very distinct; they crown the irregularities of the thallus. In site and external 
appearance they resemble those of Lecanora subfusca, though they are smaller and less 
distinct. Their cavity is simple, their walls of light-brown cellular tissue. The sterig- 
mata are also those common in L. subfusca, subcolumnar, measuring 435; in length with 
spermatia attached. The latter are of the type, straightish or curved while attached, 
becoming vermiform when free; they measure 1455 X 35455 tO 3050 X 15500, and are, 
as usual, very delicate or slender. 
Specimen 15. Var. eleochroma. On old bark, near the Upper Lake, Killarney, Mar. 
1858: Carroll Associated with Z. disciformis. Spermogones abound as small dots, 
seated in the centre of the frustules of the thallus, colourless or brown, becoming brown 
or black with age, flattened when dry, becoming pellucid and eonvex under moisture; 
the body, as usual, immersed. Spermatia are of the type, about 3%5 X 55305; the 
sterigmata also of the type. L. parasema and L. disciformis often grow together, and, 
externally, their apothecia and spermogones are frequently undistinguishable. "They are 
therefore apt to be confounded where mere naked-eye characters are trusted to. But 
the sporidia on the one hand, and the spermatia on the other, constitute excellent and 
conclusive distinguishing characters. As regards the spermatia, while they are long and 
vermiform in parasema, they are short and straight in disciformis. 
Specimen 16. Var. eleochroma. On bark, Yorkshire, Oct. 1857: Dr. Carrington. 
Spermogones are plentiful as minute, round, brown dots, seattered over the thallus. With 
their contents, they possess the characters of the type, from which it is most unnecessary 
to separate eleochroma or enteroleuca, even as varieties. 
Specimen 17. Var eleochroma. On bark, near Shrewsbury, Shropshire: Leight. Exs. 
No. 126. Spermogones occur on small, young patches of thallus, mostly on the areolæ, 
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