106 
Septobasidium was abundant on Pandanus, 
but the fungus was found on none but the 
latter plant. Parts of all collections have 
been sent to Dr. J. N. Couch, who will dis¬ 
cuss the fungus in a future publication of 
his. 
30 . Pellicularia isabellina (Fries) 
Rogers, Farlowia 1: 99, 1943. Hypochnus 
isabellinus (Fries) Fries; Burt, Mo. Bot. 
Gard. Ann. 3: 222, fig. 12, 1916. Tomen- 
tella isabellina (Fries) Hohn. and Litsch.; 
Bourd. and Galz., Hym. Fr. 482, fig. 121 
[1928]. Botryobasidium isabellinum (Fries) 
Rogers, Iowa Univ. Studies in Nat. Hist. 17: 
11, pi. 2, fig. 5, 1935. 
On wood, husks, and dead leaf-sheaths of 
Cocos nucijera, and on old polypore. Ailuk: 
Ailuk I., 1738; Mejit, 1443, 1312; Likiep: 
Eniarmij I., 1690; Namu: Leuen I., 1419; 
Jaluit, 1604. 
A delicate ochraceous tomentose growth, 
under the lens minutely tufted, under the 
microscope composed of stout, short-celled 
hyphae branching at right angles, of rough- 
walled subglobose spores, and of obpyriform 
basidia. The mature spores are thin-walled 
when abstricted; but in the Namu specimen, 
and to a slighter extent in others also, the 
wall soon becomes considerably thickened. 
I have seen one other similar tropical col¬ 
lection. 
31. Pellicularia lembospora Rogers, 
Farlowia 1: 109, fig. 8, 1943. 
On bark of rotten log of Ochrosia parvi- 
flora. Likiep: Biebi I., 1672. 
A cream-colored, very slight and loose, 
hypochnoid growth; distinguishable under 
the microscope by its small navicular spores 
mostly 7-8 X 3 /x. The collection consists of 
a few minute pallid patches of this, the per¬ 
fect stage, scattered among the much more 
robust, tawny, imperfect fructification of 
the same fungus. See under Oidium tomen- 
tosum, below. Previously reported from 
British Guiana and Cuba, and present also 
PACIFIC SCIENCE, Vol. 1, April, 1947 
in Hawaii; a tropical relative of the more 
nearly ubiquitous P. vaga. 
32. Pellicularia vaga (Berk, and 
Curt.) Rogers, Farlowia 1: 110, fig. 9, 1943. 
Corticium botryosum Bres.; Bourd. and 
Galz., Hym. Fr., 241 [1928]. 
On bark, wood, and husks of Cocos nuci¬ 
jera, and wood of Pandanus sp., Artocarpus 
incisus, and an undetermined dicot. Utirik, 
1439, 1801; Ailuk: Ailuk I., 1703, 1746, 
1737; Mejit, 1447, 1448, 1310, 1313, 1320; 
Likiep: Likiep L, 1477; Wotje: Ormed I., 
1370, 1343; Jaluit, 1613. 
A pallid or buff hypochnoid growth with 
the characteristic very wide mycelium of the 
genus and naviculiform spores (fusoid, de¬ 
pressed on one side) mostly 10-12 X 4.5 /x. 
The commonest member of the genus in the 
Marshalls, as on the northeastern and north¬ 
western coasts of the American mainland 
and, apparently, in western Europe. 
Fungi imperfecti 
33. Helicomyces roseus Link; Linder, 
Mo. Bot. Gard. Ann. 16: 271, pi. 12, fig. 
5-7, 1929. 
On husks of Cocos nucijera. Ebon, 
IX.10.46, 1803 (with 1338). 
A grayish bloom, imperceptible except 
under considerable magnification, composed 
of hyaline linear conidia coiled like a watch- 
spring, and very short hyaline conidiophores. 
The fungus was discovered only when the 
specimen earlier cited of Sebacina jar inace a 
was being examined under the binocular. It 
is less conspicuous macroscopically than the 
quite inconspicuous Iowa specimens, deter¬ 
mined by Linder, with which it was com¬ 
pared, but agrees in all other respects. 
34. Oidium tomentosum (Berk, and 
Curt.) Linder, Lloydia 5: 204, pi. 5, fig. E, 
1942. 
On bark of rotten log of Ochrosia parvi- 
jlora and unidentified dicot wood. Likiep: 
Biebi I., 1672, 1674. 
