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SPERMOGONIA 201
paraphyses, and also in Steganosporium cellulosum (Melanconieae). These
observations have been confirmed by Allescher 1 in his recent work on Fungi
Imperfecti. Keiszler 2 has described a P/wma-\ike pycnidium parasitic on
the leprose thallus of Haematomma elatinum. It contains short slender
sporophores and, mixed with these, long branched sterile hyphae which
reach to the ostiole and evidently function as paraphyses, though Keiszler
suggests that they may be a second form of sporophore that has become
sterile. On account of their presence he placed the fungus in a new genus
L icJienophoma.
E. SPERMATIA OR PYCNIDIOSPORES
a. ORIGIN AND FORM OF SPERMATIA. Lichen spermatia arise at the
tips of the sterigmata either through simple abstriction or by budding. In
the former case as in the Squamaria type a delicate cross-wall is formed
by which the spermatium is separated off. When they arise by budding,
there is first a small clavate sac r like swelling of the end of the short process or
sterigma which gradually grows out into a spermatium on a very narrow base.
This latter formation occurs in the Sticta, Physcia and Endocarpon types.
Ny lander 3 has distinguished the following forms of spermatia:
1. Ob-clavate, the ^road end attached to the sterigma as in Usneae,
Cetraria glauca and C. juniperina.
2. Acicular and minute but slightly swollen at each end, somewhat
dumb-bell like, in Cetraria nivalis, C. cucullata, Alectoria, Evernia and some
Parmeliae, frequently borne on "arthrosterigmata."
3. Acicular, cylindrical and straight, the most common form ; these occur
in most of the Lecanorae, Cladoniae, Lecideae, Graphideae, Pyrenocarpeae
and occasionally they are budded off from arthrosterigmata.
4. Acicular, cylindrical, bent; sometimes these are very long, measuring
up to 40 //.; they are found in various Lecideae, Lecanorae, Graphideae,
Pyrenocarpeae, and also in Roccella, Pilophorus and species of Stereocaulon.
5. Ellipsoid or oblong and generally very minute; they are borne on
simple sterigmata and are characteristic of the genera Calicium, Chaenotheca,
Lichina,Ephebe,ofi\\e. small genus Glypholecia and of a few species tfLecanora
and Lecidea.
In many instances there is more or less variation of form and of size in
the species or even in the individual. There are no spherical spermatia.
b. SIZE AND STRUCTURE. The shortest spermatia in any of our British
lichens are those of Lichina pygmaea which are about i'4/A in length and
In width
the longest are those of Lecanora crassa which measure up to 39 ft.
they vary from about O'5/tt to 2/z. The mature is filled spermogonium with
1 Allescher 1901-3.
2 Keiszler 1911.
3 Nylander 1858, p. 37-