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PACIFIC SCIENCE, Vol. XV, October 1961 
reef, which lies many feet from the islet’s shore. 
No rainfall records are available; however, the 
inner forest with its better development of soil- 
and tree-cover no doubt accumulates moisture 
and retains it longer than the grassland and 
fringe area, with their porous volcanic boulders. 
1, Fringe Area. A, Upper story: *Desmodium 
umbellatum (L.) DC., common, the trunk to 10 
cm. diameter; *Colubrina asiatica (L. ) Brongn., 
common, shrubby; *Clerodendron inerme (L.) 
Gaertn., common scandent shrub; * Callicarpa 
candicans (Burm.) Hochr., scattered; *Barring- 
tonia asiatica (L.) Kurz, scarce, only small plants 
seen; * Guettarda speciosa L., only on south side; 
* Allophylus timorensis (DC.) BE, on south side; 
* Ficus sp., on south side; *Premna obtusifolia 
R. Br„, on south side only; *W edelia biflora 
(L.) DC. ex Wight, scandent shrub; *Morinda 
citrifolia L. — B, Vines: Abrus precatorius L.; 
*lpomoea digitata L.; *Passiflora foetida L.; 
Dios corea sp.; *lpomoea pes-caprae L., only one 
plant seen, in a small area; * Denis elliptica 
(Roxb. ) Bentham. — C, Ground cover: * Micro - 
sorum scolopendria (Burm.) Copel.; V ernonia 
cinerea (L. ) Less.; Echinochloa colonum (L.) 
Link; *'Tacca leontopetaloides (L.) Ktze., scat- 
tered and rare; *Digitaria pruriens ( Erin .) Biise. 
— D. Epiphytes: * Asplenium sp.; *Davallia 
solida (Forst. ) Sw.; *Dendrobium sp. 
2, Grassland. A, Herbaceous cover, extreme 
eastern end of islet: *Digitaria pruriens (Trin.) 
Biise; P asp alum dilatatum (?); Chrysopogon 
aciculatus (Retz.) Trin.; Paspalum conjugatum 
Berg.; Cyperus sp.; *Fimbristylis atollensis St. 
John; Emilia sonchifolia DC.; P hyllanthus 
amarus Schum. & Thonn.; *Portulaca samoensis 
v. Poelln.; * Micro sorum scolopendria (Burm.) 
Copel., a dwarf form. — B, Transitional zone, 
with shrubs; merging with 3: Desmodium sp. 
(seedlings); Eledychium coronarium Koen. & 
Retz.; *Barringtonia asiatica (L.) Kurz, one 
seedling; *Tacca leontopetaloides (L. ) Ktze.; 
Abrus precatorius L.; *Premna obtusifolia R. 
Br.; *Passiflora foetida L.; Abelmoschus sp.; 
Capsicum frutescens L.; Cocos nucifera L.(a few 
young trees); *Morinda citrifolia L.; *Colub- 
rina asiatica (L. ) Brongn.; * Canavalia micro- 
carpa (DC.) Piper. 
* Species marked with an asterisk are indigenous. 
3, Inner Upland Forest Area. — A, Trees: 
Mangifera indica L.; Musa balbisiana X acumi- 
nata; Carica Papaya L.; *? Eerminalia catappa 
L.; # Ficus tinctoria Forst.; Erythrina variegata 
L.; Cocos nucifera L. — B, Shrubs: *Colubrina 
asiatica (L. ) Brongn.; *Morinda citrifolia L.; 
*Glochidion ramiflorum Forst.; *Polyscias 
grandifolia Volkens. — C, Ground cover: *Op- 
lismenus compositus (L.) Beauv.; Paspalum con- 
jugatum Berg.; P. dilatatum ( ? ) . — D, Vines: 
* Canavalia microcarpa (DC.) Piper; Abrus pre- 
catorius L.; * Piper fragile Benth. — E, Epiphytes: 
*Davallia solida (Forst.) Sw.; * Microsorum 
scolopendria (Burm.) Copel. 
All plants mentioned are represented by speci- 
mens in possession of the senior author. 
animals PRESENT: The terrestrial animals, 
excluding insects and other invertebrates, were 
noted and identified by William R. Newman. 
Two species of lizard were fairly common, 
Emoya cyanura and E. boetgeri. The birds noted 
were Aplonis opacus angus, the Micronesian 
starling; Demigretta sacra sacra , the reef heron 
( dark phase ) ; Myzomela cardinalis major, the 
cardinal honey-eater; Collocalis inquieta ruken- 
sis, the Carolines swiftlet; and Gygis alba, the 
fairy tern. 
SUMMARY 
The small volcanic islet in Truk Lagoon called 
Yanagi is remarkable for the lack of coralline 
development and the lack of halophytic vegeta- 
tion which are common elsewhere on Truk. 
The vegetation appears to comprise three zones, 
which are called the fringe area, the grassland 
area, and the upper inland forest. The summit is 
about 30 ft. above sea level, and the islet is sur- 
rounded by a reef. Though occupied during the 
war, the vegetation is now fairly recovered from 
disturbance. A list of the plants occurring in 
each vegetation zone, and a brief note on some 
animals observed, is given. 
REFERENCE 
Mayr, E. 1945. Birds of the South-West Pacific. 
Macmillan, N.Y. 
