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PACIFIC SCIENCE, Vol. Ill, October, 1949 
name and placed it in Alectryon. His descrip- 
tion is very brief, mentioning only that the 
large, usually 1 -celled fruit is 3 cm. in diameter; 
the leaflets up to 26 cm. in length, 11 cm. wide; 
and that the hypodermis of the lower leaf sur- 
face is distinctive. Though these few characters 
could have been selected from the lengthy des- 
cription given by Hillebrand, it is certain that 
Radlkofer studied the Hillebrand specimens in 
Berlin, for the Hillebrand sheet with a leaf and 
old fruiting branches, labeled "Mahoe, pali of 
Koolaupapa, Molokai.” bore the note in Radl- 
kofer’s writing, "Alectryon macrococcus m. [ihi] 
Radik.” We now designate this Hillebrand sheet 
in the Berlin Herbarium as the lectotype of 
A. macrococcus Radik. It was probably destroyed 
in the bombing of Berlin in 1943, but Figure 3 
Fig. 3. Alectryon macrococcus: photo of lectotype 
in Berlin Herbarium, "pali of Koolaupapa," Molokai, 
Hillebrand. 
Fig. 4. Alectryon macrococcus: flower, Haleakala, 
Maui, 2,600 ft., J. F. Rock, Nov. 1910, X 10. 
shows the sheet as it appeared when photo- 
graphed by St. John in 1935. 
A . macrococcus Radik, of Molokai is distin- 
guished by having the leaflets 11-18.5 cm. 
long, lance-elliptic, densely soft yellowish pilo- 
sulous below; perfect flowers with the calyx cam- 
panulate (Fig. 4); style scarcely evident; the 
stigmas short, erect, not diverging. The collec- 
tions from Maui are very similar and are con- 
firmed as conspecific with the true A. macrococ- 
cus of Molokai, and they furnish perfect flowers, 
with anthers only 0.5 mm. long. 
In contrast, we find that A. Mahoe has the 
leaflets 9-26 cm. long, commonly elliptic (or 
slightly lance- or oblance-elliptic, rarely oval), 
except for the main veins the lower surface 
glabrous; perfect flowers with the calyx knee- 
pan-shaped, the base truncate ( Fig. 1 ) ; anthers 
1. 1-1.5 mm. long; style slender, evident. These 
differences seem sufficient to justify the separa- 
tion of the Oahu plant as a new species. Its 
specific name is the Hawaiian vernacular one, 
"mahoe,” meaning twins, in allusion to the 
often twinned fruit. 
The illustration by Degener in his Flora Ha- 
waiiensis of material which he called A. mac- 
rococcus from Makua, Oahu, is a good represen- 
tation of fruiting A. Mahoe , but his description 
is a composite of the two Hawaiian species. 
There are in the Bishop Museum two sheets 
of a collection from the island of Kauai: Olokele 
Valley, J. M. Lydgate, with stems, leaves, and a 
