у w FW I 
CYANOPHYCEAE 
Family CHROOCOCCACEAE 
PLACOMA Schousb.; Born. & Thur. Not. Alg. 4. 1876 
PLACOMA sp. 
Thallus forming pulvinate or irregularly hemispheric, simple 
or sparingly lobed or corrugate, usually isolated vesicles mostly 
0.5-1.5 mm. in diameter; walls of the vesicles 25-50 и thick, with 
occasional scattered сеѕюссируіпе the central slime-filled cavity, 
the outer jelly 8-14 и thick; cells (endochrome) after division 
concavo-hemispheric or tetrahedral-hemispheric, later reniform, 
lunate, oblong-ellipsoidal, or subspheric, 5.5-13 и in long diam- 
eter, the gelatinous walls diaphanous, rather soft and confluent. 
On a water-born basal fragment of Prionitis decipiens, in com- 
pany with other epiphytes, washed ashore, La Punta, region of 
Callao, Dec. 6, 1906, Coker 23 p.p. 
Near the rupicolous Расота vesiculosa Schousb. of northern 
Africa and southern Europe, yet seems to differ in the smaller 
simpler thallus, the thinner wall of the vesicle (100-130 и thick in 
P. vesiculosa according to Bornet's figures*), and the softer more 
confluent and less well-defined cell walls. The color is green 
with a slight trace of blue, but this character may have been modi- 
fied by the preserving fluid (formalin). Тһе fresh-water Placoma 
africana Wille has much smaller cells and a more parenchymatous 
structure. 
We have had no authentic specimens of Placoma vesiculosa for 
comparison, our Peruvian material is scanty, and we would not 
venture at this time to assign to it any specific name. 
CHLOROGLOEA Wille, Nyt Mag. Naturvid. 38: 2-5. 1900 
CHLOROGLOEA TUBERCULOSA (Hansg.) Wille, loc. cit. 
Pi. r.f i 
Palmella (?) tuberculosa Hansg. Sitzungsb. Königl. Böhm. Ges. 
Wiss. 1892: 240. pl. б. f. 9. 
ж Born. & Thur. Not. Alg. pl. r. f. 6—10. 
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