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PACIFIC SCIENCE, Vol. XV, January 1961 
Fig. 12. Distinction of various habitats based upon vegetation and topography. 
Adults and nymphs of all stages of Locusta 
were collected on M esserschmidia. From their 
extreme abundance, high activity, and great vo- 
racity, I have the impression that this popula- 
tion might change from phasis solitaria to phasis 
transiens. Inside still younger buds of Messer- 
schmidia, a small cricket, Ornehius, was often 
discovered. They always directed the head and 
antennae upward (Fig. 15), and when dis- 
turbed rolled down very quickly into the earth. 
Coccus were also found in Pisonia and, espe- 
cially in papaya, were eagerly visited by two 
milkers, Lasius and Tapinoma. Moreover, vari- 
ous flies and their predators, Heteropoda and 
Neoscona, were abundant throughout the arbo- 
real foliage. Considerable numbers of the latter 
species were found in nests of an introduced 
American wasp, Sceliphron. 
Corresponding to their ecotonal nature, B 
and C were relatively rich in number of species 
but possessed only two characteristic bugs: 
Cyrtopeltis on tobacco and Liorhyssus on Son- 
chus. The activities of skinks and land crabs 
decrease in B due to a relatively thick growth 
of herbs and grass but increase again in C. The 
most characteristic species in these transient 
zones is Aiolopus, which, in contrast to its 
cousin, Locusta , does not invade zone A. 
Aphis and its predator, Ischiodon, were found 
in this zone on Portulaca, the dominant plant 
in C and D, although the former species was 
found in zone A as milk cows inside a nest of 
Tetramorium. Solenopsis was also found only 
in this zone. 
With the further decrease of plant cover, 
animals adapted to bare surfaces appeared in D. 
The characteristic species was Oligotoma, which 
was extremely abundant in runways and adjacent 
exposed areas, dwelling in a characteristic nest 
spun by themselves (Fig. 16). If they were 
driven away from the nest, they were hunted 
by Lasius as soon as they were discovered by 
this ant. At night, winged adults were collected 
around the lamps situated near the runway. 
Zones C and D' are reproductions of C and 
D in the littoral zone. A characteristic animal 
assemblage was collected under the stones and 
large gravels in CT : it consisted of Geogarypus , 
an oribatid mite, two collembola, myriapods, 
etc. On exposed surfaces, however, there were 
very few animals, except for Lasius and Tapin- 
oma walking on the runners of Ipomoea. D\ 
especially, was macroscopically a complete abio- 
tic zone. The only animals collected were An - 
isolahis, found under the decayed matter. Al- 
though it did not belong to the land biota, an 
endemic marine collembola, Polyacanthella oce - 
anica Uchida, was discovered at the northern 
rocky reef of the NW. shore, together with 
some polychaetes, crabs, etc. According to a 
