18 
well with such European specimens asI possess of 
Dirina Ceratonia; which differs also in its much 
larger, broad-fusiform spores. 
Puacopium coralloides, Tuck. (*) Coast ; Mr. Bolander. 
P. cladodes, Tuck. Rocky Mountains ; Mr. Hall. 
P. elegans (Link) DC. Rocky Mountains; Mr. Hall. 
Dr. Parry. 
P. callopismum (Ach.) Merat? Coast; Mr. Bolander. 
P. fulgens (Sw.) DC. Rocky Mountains; Dr. Hayden. 
Piacopium bolacinum (sp. nova) thallo squamuioso 
fulvo, squamis glebulosis rotundatis levgatis subinde 
erenatis ; apothecus mediocribus zeormis subplanis disco 
aurantiaco. Spore octone, polari-dyblaste, diam. sub- 
duplo longiores, incolores. Sandstone bowlders, on 
the coast, Mr. Bolander; who finds a similar lichen 
on mud walls. ; 
P. cinnabarrinum (Ach.) Anz. Coast; Mr. Bolander. 
Piacopium Jluteo-minium (sp. nova) thallo crustaceo 
glebuloso lutescente ; apothecus mediocribus biatorinis ex 
aurantiaco mimatis, disco plano, margine ruguloso. 
Spore 8-16ne, oblonge dein fabaformes, dyblaste 
sporobl. approxvmatis isthmo deficiente, diam. 23 plo 33 
plo longiores, incolores. On the earth, San Diego; Dr. 
J. G. Cooper. Spores larger and more regular than 
those of the next, from which the colours sufficiently 
distinguish the present. 

(*) Adopting here, as already in Obs. Lich. (7. c. 6, p. 266, 
287) the general views of Dr. Stizenberger (Beitr. 7. c. p. 135) 
as to the systematic value of the effigurate type of thallus, I can- 
not hesitate to arrange with this last its fruticulose exaltation, 
so remarkably exhibited on the west Coast. The oniy known 
example of this type was Lecanora fruticulosa Eversm. (Spharo- 
thallia, Fr. Nees, prop.) but this 1s distinguishable, as a mem- 
ber of the section Aspicilia, from ZL. Bolanderi, &c.; and the 
latter cluster may take the sub-sectional designation of Clado- 
dium: as Placodiwm coralloides and cladodes 0: Thamnoma. 
