71 
erescences starting from the inner wall, such as occur so fre- 
quently in Acarida- 
galls, are not deve- 
loped here. Occasio- 
nally the galls are si- 
tuated on the underside. 
The host-plant is very 
common in Java and 
grows preferably on 
newly cleared grounds. 
On Krakatau its favou- 
rite habitat was the 
Casuarine-forest. In 
the list of plants, col- 
lected on Krakatau by 
Ernst the name of this 
plant does not figure, 
but it is to be found in the index of Vaueton, who collected 
there in 1904. At the present time the plant is very general 
there. Of Verlaten-Eiland she is mentioned by Backer as found 
during his second visit in 1908. On Verlaten-Eiland, where the 
plant also occurs abundantly, I could not find a single speci- 
men of this gall during my first visit in April 1919. 
During the excursion made to this island in early October 
by the members of the Congress of Natural Sciences, I found 
a few plants bearing this gall, in the very place where I had 
carefully looked for these galls in April last, without then finding 
any. Perhaps I may have conveyed the parasite myself from one 
island (Krakatau) to the other, for on that occasion Verlaten- 
Kiland was visited by me on the same day as Krakatau, anditis 
- quite possible that the gall-producers were on my clothes or 
were carried along in my vasculum. 
_ The gall-producer has been described by Nazepa > 
Fig. 9. Macoranga Tanarius L. 
Island of Krakatau near the coast and in ravines up to aif: — e 
tudes of about 300° ft. above sea-level. 
1919. Jorenen Seed ene iN. 3833, ( ae at ss _ ae 
Herb. N°. 3508, April 24th 1919; Herb. N°. April 25th 
