An Investigation of Hematochrome Accumulation in the Alga 
Phycopeltis hawaiiensis n. sp/ 
John W. King^ 
The production and accumulation of 
hematochrome, an orange-red pigment com- 
monly found in the cells of Trentepohliaceae, 
are thought to depend upon certain external 
environmental conditions, as well as upon 
the physiological activity of the cells. Accord- 
ing to Senn (1911) and Geitler (1923), the 
accumulation of hematochrome depends upon 
the quality and intensity of the light reaching 
the cells, food supply, moisture, and rate of 
growth. Senn points out that, in nutritive 
mineral solutions encouraging active growth, 
the amount of hematochrome pigment is 
greatly diminished. In this investigation an 
attempt was made to determine whether or 
not there is a correlation between rate of 
growth and hematochrome accumulation in 
a heretofore undescribed species of Phycopeltis 
found on the campus of the University of 
Hawaii. 
Phycopeltis hawaiiensis n. sp. 
Hematochrome orange-red; thallus circular 
with two concentric areas differing in hue; 
margin entire; filaments branching; no spo- 
rangia or gametangia produced. 
Thallus aurantiaciacus discoideus, centro et 
regio concentrico exteriore in colore distincte 
gradato, margine integro, filamentis ramosis 
saepe oppositis sed trichotomo-simulantibus, 
est. Sporangia et gametangia desunt. 
Holotype, a preparation of material col- 
lected June 12, 1953, on the campus of the 
University of Hawaii, is deposited in the 
Bernice P. Bishop Museum in Honolulu. 
1 Research carried on in the Department of Botany, 
University of Hawaii. Manuscript received June 19, 
1953. 
2 Morgan State College, Baltimore, Maryland. 
Isotypes will be distributed through the 
Museum. 
METHOD OF CULTURING PHYCOPELTIS 
Phycopeltis used in this investigation was 
found growing on the leaves of a member of 
the Araliaceae on the campus of the University 
of Hawaii. In damp, shaded environments the 
alga reaches its ultimate state of development, 
forming numerous orange-colored, cushion- 
like discs on leaves. Upon microscopic ex- 
amination of a disc, the presence of fungal 
hyphae living in close association with the 
alga is revealed. In culture the fungal hyphae 
can be seen intermingled with the algal fila- 
ments. This condition has led many investi- 
gators to consider Phycopeltis to be a lichen. 
Discs were carefully removed from leaves 
and placed on different sterile media as shown 
in Table 1. All media contained a base of 1 
per cent Knop’s nutrient solution (Bold) in 
2 per cent agar. The algae were then cultured 
under natural daylight conditions. The cul- 
tures were observed each day under a wide- 
angle microscope, to discover whether new 
filaments had developed from the discs. 
It is observed from Table 1 that the most 
rapid growth took place when Phycopeltis was 
cultured on a medium containing Knop’s 
nutrient solution in 2 per cent agar. The pres- 
ence of sucrose or juice from the leaves upon 
which the epiphyte grew in the medium re- 
duced the growth rate during the period 
immediately following inoculation. However, 
at the end of 80 days all media had produced 
considerable growth except those containing 
Knop’s solution in agar, juice from leaves 
upon which the epiphyte was growing, and 
sucrose. Since Knop’s nutrient solution in 
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