(110) 
cilia; and the tri-quadrilocular spores of P. Brebissonii (Fée) and 
P. spadiceum, Tuckerm. Lich. Hawaii, as an anticipation and illustration 
of the analogous evolution of the spore-type of Lecanora, in the section 
Lecania. The polar sub-type becomes quadrilocular in Theloschistes also 
(in Physcia hypoglauca, Nyl.): but with this stage our present knowledge 
of the evolution of this kind of spore ceases. 
XXVIII.—LECANORA (Ach.). 
Ach. L. U. p. 77, pro magna p., et Urceolariz sp., p. 74. Stizenb. Beitr. 
1. c. p. 169, et Acarospora max. p., p. 168, et Lecania pr. p.170. Nyl. 
Lich. Scand. p. 139, max. p., et Squamaria, p. 130. Parmelia, b, Pla- 
cothalle p. magna p., Fr.Summ. p.105. Parmelia, sectt. 1, Placodium 
max. p., 2, Psora, 3, Patellaria max p., et 4, Urceolaria pr. p., et Bia- 
tore sp., Tuckerm. Syn. N. Eng. p. 37, &c. Parmelia pr. p., Amyg- 
dalaria, et Ophioparma, Norm. Con. pp. 15, 18, t. 1, f 8, 9, 11. 
Squamaria, Lecania pr. p., Lecanora, Hematomma, Acarospora, et 
Aspicilia, Mudd. Man. Brit. Lich. p. 127, &c. Placodium, Lecanora, 
Lecania pr. p., et Biatorze spp., Mill. Principes de Classif. p. 37, &c. 
Gussonea, Pleopsidium, Psoroma pr. p., Ochrolechia, Zeora, Polyozo- 
sia, Pachyospora, Lecanidium, Dimerospora, et Sarcogyne, Auctt. 
Structuram descripserunt Tulasne, Mém. sur les Lich. p. 150, 152, 
158, 191, t. 3, 4, f. 15-22, 10, f. 19-23, 13, f. 18-23; Fuisting de nonnull. 
apoth. pp. 10, 33. 
Apothecia scutelleformia, margine nunc composito. Spore ex 
ellipsoideo oblong, simplices, rarissime bi-quadri-loculares, 1. elon- 
gato-fusiformes pluriloculares, incolores. Spermatia 1. oblonga 1. 
bacillaria, 1. acicularia arcuata; sterigmatibus sub-simplicibus. Thal- 
lus crustaceus, aut effiguratus aut rarissime papilloso-fruticulosus 
aut uniformis. 
Excluding the immediately preceding group (Placodiwn) and the next 
following one (Rinodina) the separation of which is determined by differ- 
ences in the spore-type, Lecanora, as here taken, embraces (exceptis 
excipiendis) the whole of the species referred to the genus by Acharius; 
and to his Parmelia sect. Placothalle (Summ. 1. ¢.) by Fries. The 
ground-idea of this construction has been best exhibited by Dr. Stizen- 
berger; but he (1. c.) distinguishes the polysporous, effigurate group 
(Acarospora, Massal.) and separates also the species with bi-plurilocular 
spores (Ophioparma, Norm. Lecania, Mass., Dimerospora, Th. Fr.). 
Nylander retains all these in Zecanora; accepting however the generical 
distinctness of the effigurate, true Lecanore (Squamaria, DC., Nyl.) he 
is led, in like manner, to include in the present genus the granulose spe- 
cies of Placodiwm. Other recent authors have assumed in their con- 
