364 
PACIFIC SCIENCE, Vol. XVII, July 1963 
Fig. 3. An "Arcade” on Admiralty Island. The greyish dots in the air are sea birds which nest there. The 
basalts form the main mass of the island. (Photo by Miss Z. Liepa.) 
1959, specimens of Optus oophilus were liber- 
ated there to control the Queensland fruit fly, 
Strumeta tryoni, and the parasite was recov- 
ered in March 1961. The small size of the 
island greatly facilitated the experiments. 
It is impossible to go into details about the 
insect fauna of the island as the available data 
are too fragmentary. However, some points are 
very significant, especially those concerning 
wingless insects (and birds); they show a close 
relationship to the New Zealand fauna and 
to the eastward land masses in general. The 
Australian element, considered numerically, 
may be larger than that of New Zealand or 
Polynesia, but the proximity of the Australian 
continent, its great extension northwards and 
southwards, and the direction of the prevailing 
winds in the southwest Pacific no doubt ac- 
count for this preponderance. If we take as an 
example the plant genera which are confined 
to Australia and Lord Howe Island (Notelaea, 
Melaleuca , Lyonsia, Lagunaria, and W estringia) , 
we must not overestimate the importance of 
this fact, because the most characteristic Aus- 
tralian genera are either- entirely absent from 
Lord Howe Island or represented by only one 
or two species. This means that these species 
have had more facilities for transportation, 
natural or by man. 
Summarizing all the data in our hands, we 
can say from its fauna that Lord Howe Island 
is not a part of the Australian zoogeographical 
region, but is closer to the New Zealand sub- 
region. 
GEOLOGY 
In order to understand the history of the 
fauna and flora the geology also must be con- 
sidered. The general geology of the island is 
very simple; the island consists mainly of two 
principal formations: the volcanic rock which 
