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POPULAR HISTORY OF LICHENS. 



Genus II. SCUTULA, Tul. 



Gen. Char. Apothecia superficial on the thallus of various fo- 

 liaceous lichens, scutiform or discoid, and immarginate. Thecse 

 clavate, 6-8-spored. Spores ovate-oblong, obtuse at ends, simple, 

 pale, full of homogeneous oil. Spermogones globose, very minute, 

 superficial, with a simple cavity. Spermatia linear, very slender, 

 short, curved, generated acrogenously from simple, oblong-acute 

 sterigmata. Pycnides globose, superficial, somewhat deplanate 

 at apex, unilocular, thick-walled. Sterigmata short and simple. 

 Stylospores oblong-cylindrical, obtuse at ends, curved, simple or 

 rarely uniseptate. (Name from scutula, a little saucer, in allu- 

 sion to the form of the apothecia.) 



Only one species is described by Tulasne, viz. — 

 1. Scutula Wallrothii (named in honour of M. 

 Wallroth, a celebrated German cryptogamist). Apothecia 

 small, disciform, flattish. Spores unilocular, ovate or ellip- 

 soid, pale. Spermogones superficial, very minute, globose. 

 Spermatia linear, curved, very delicate. Pycnides in form 

 and site are similar to the spermogones ; in structure they 

 resemble those of the genus Abrotliallus. Sterigmata linear- 

 conical, simple. Stylospores oblong, straight or slightly 

 curved, simple, rarely bilocular. 



Tulasne mentions its occurring on various specimens of 

 Peltigera canina from Germany and France. 



