Studies in the Hawaiian Rutaceae, IV 
New and Critical Species of Pelea A. Gray 1 
Benjamin C. Stone 2 
The following notes, including descriptions 
of four proposed new species, are the partial 
outcome of monographic studies of Hawaiian 
genera. Pelea is a genus confined to the Hawai- 
ian and Marquesan archipelagoes, with all but 
two of its species endemic to the Hawaiian 
Islands. There*are four relatively natural sections 
of the genus, characterized primarily by features 
of the mature fruits and to a lesser extent by 
leaf arrangement. Systematic treatment of sec- 
tion Pelea , which includes the type species, Pelea 
clusiaefolia, is completed. The following notes 
apply to sections Apocarpa, Megacarpa, and 
Cubicarpa, as defined by the writer (Stone in 
Degener, 1962 ) . Related studies have recently 
appeared or are now in press (Stone 1962^, 
1962b, Stone in Degener, 1962). Casual collect- 
ing of species of Pelea was begun by the author 
in 1955; in 1958 and 1959 and summer, 1961, 
intensive field and herbarium studies were car- 
ried out. Through the courtesy of the U. S. Na- 
tional Herbarium, Smithsonian Institution, loans 
of historically important collections were ob- 
tained, and I am grateful to Dr. H. R. Fletcher, 
of the Royal Botanic Gardens, Edinburgh, Dr. 
George Taylor of the Royal Botanic Gardens, 
Kew, Dr. J. E. Dandy of the British Museum 
(Natural History), Dr. Alicia Lourteig of the 
Museum d’Histoire Naturelle, Paris, Dr. Richard 
A. Howard of the Arnold Arboretum of Harvard 
University, and Dr. A. J. Eames of Cornell Uni- 
versity for their aid. I am particularly indebted 
to the former Director of the Bishop Museum, 
Dr. Alexander Spoehr, Botanist Marie C. Neal, 
and Curator of Collections E. H. Bryan, Jr., for 
their generous assistance. 
The following comments are arranged by ge- 
neric section. 
1 The greater part of this work was accomplished at 
the University of Hawaii and at the U. S. National 
Herbarium. Manuscript received February 27, 1962. 
2 College of Guam, Agana, Guam. 
SECTION Apocarpa STONE 
1. Pelea ovata St. John & Hume in Lloydia 7: 
272, 1944. 
P. Forbesii St. John & Hume, l.c. Syn. nov. 
Examination of the holotype specimens shows 
that the pubescence which is found on Forbes 
369.K, the type of P. Forbesii, is not constant, 
but is found only on one leaf, perhaps from an 
abnormal cause. It has been noted that leaf-galls 
of other species, even ordinarily glabrous ones, 
will often be densely puberulent. Even the new 
leaves and buds of P. Forbesii are found to be 
glabrous. Since no other character or combina- 
tion of characters appears to distinguish this 
from Pelea ovata, it is concluded that but one 
species is represented. Since the description of 
P. ovata calls for glabrous leaves, and since there 
is no question of priority involved, both descrip- 
tions first appearing on the same page of the 
publication, the name P. Forbesii is relegated to 
synonymy. 
Pelea ovata is a vinelike shrub endemic to the 
island of Kauai. 
2. Pelea hawaiensis Wawra in Flora 56:110. 
1873. 
P. cinerea var. y Hillebrand, FI. Haw. Ids. 69, 
1888; Rock, Indig. Trees Haw. Ids. 239, 
I 913 (in part, excluding Oahu plants). 
P. cinerea var. hawaiensis (Wawra) Rock in 
Bot. Gaz. 65:265, 1918. 
A tree with smooth light-brown bark, op- 
posite leaves, and generally pubescent innova- 
tions; the pubescence of fulvous or reddish hairs, 
rarely pale; petioles, twigs, and leaves sometimes 
soon glabrate, commonly with a more or less per- 
sistent indument; inflorescences usually densely 
puberulent, or tomentose, cymose, with generally 
3 to 27 flowers, axillary; flowers with deltoid 
acute thick tomentellous sepals; petals deltoid- 
407 
