34 
PACIFIC SCIENCE, Vol. XIII, January 1959 
It may be coincidental that the Subtropical 
species have proved adequate to indicate the 
waters of subtropical origin from both east 
and west of New Zealand, If further investi- 
gation shows that the faunas are dissimilar, 
separate indicator groups would probably 
need to be established for the waters of each 
of these areas. 
Coastal Group 
Species indigenous to coastal waters must 
necessarily be tolerant of the considerable 
fluctuations in temperature and salinity which 
may occur in these waters. The species of the 
Coastal Group are distinguished from the 
Subtropical Group by occurring over a much 
wider range of temperatures (Figs. 8, 9). Six 
species have been selected, namely Tenagomysis 
macropsis Tattersall, T. tenuipes Tattersall, Pa- 
rathemisto {Euthemisto) gracilipes Norman, P. 
(P.) australis Stebbing, Nyctiphanes australis 
Sars, and Oikopleura dioica Fob Nyctiphanes 
australis is a recognised coastal species 
(Sheard, 1953), as is 0. dioica (Thompson, 
1948). Tenagomysis spp. have been confined 
almost completely to neritic conditions (Tat- 
tersall, 1918, 1923; Bary, 1956). Parathe- 
misto australis has been collected previously 
only in coastal areas (Stebbing, 1888; Barnard, 
1930), which is true of the present material 
(Hurley, 19^^) . Par athemisto gracilipes occmt^d 
in similar localities to, and was often captured 
with, P. australis, although the literature de- 
scribes it as an oceanic species. Of these spe- 
cies only one specimen of N. australis was 
captured in water of unquestioned subantarc- 
tic origin (Station 212, Fig. 9), presumably as 
a stray. On the other hand, all species were 
present very commonly at stations where 
subantarctic water is believed to have been 
mixing with coastal water (Stations 292, 310, 
330, etc., and Stations 189, 190, 125). A few 
specimens of Parathemisto spp. were taken at 
Station 322— suggestive of coastal water at 
the station. The occurrences of Coastal spe- 
cies at Stations 124 and 128 are not incon- 
sistent. These stations lie in highly saline 
water which appears to be originating in a 
large shallow inlet on the north coast of 
Stewart Island (Patterson Inlet, Figs. 1, 12), 
and it is this water which locates the stations 
in the part of the diagram representing sub- 
tropical water (Fig. 3). 
There is a general, but patchy, distribution 
of Coastal species throughout the coastal 
water, from high to low salinities and up to 
the highest temperatures. Nevertheless, they 
are almost completely absent from subantarc- 
tic water, even when it is contiguous with 
coastal water. It is believed that the species 
either are unable to survive being transferred 
from the coastal into subantarctic water, or 
that some physical process at the boundary 
between the waters prevents such a transfer 
(see pp. 48-49). 
INTERRELATIONSHIPS BETWEEN SPECIES’ 
GROUPS, AND TEMPERATURES AND SALINITIES 
The interrelationships of the species’ groups 
and their correlation with temperatures and 
salinities are shown in Figure 10. The groups 
are distinguished in the figure by hatching, 
and a subjective estimate of the abundance of 
each is indicated. The "area of chief concen- 
tration’’ is demarcated by lining-in and rep- 
resents that portion of the diagram in which 
the bulk of each of the groups was captured. 
As particular organisms are undoubtedly 
characteristic of particular waters, those in- 
stances where species from several waters are 
found together are believed to represent areas 
of mixing waters. Figure 10 illustrates that 
there are aggregations of stations (already 
referred to) from which large mixed catches 
were consistently made. Stations 292, 330, 
310, 279, 304, 40, and 79 (refer also to Fig. 3) 
form one aggregation and Stations 189, 190, 
and 125 another. All four species’ groups were 
present at most stations of the first aggregate, 
which indicates that the collections are from a 
mixture of the three waters. Subtropical spe- 
cies were absent from stations of the second 
