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SoME INSECTS OF THE BETWEEN TIDES ZONE. 
CHARLES H. ARNDT. 
All insects, except a few species which live entirely in the water and 
have functional gills, are air breathing animals, breathing by means of 
trachee. Thus we may desire to know how air breathing insects living 
in 2 zone which is submerged twice a day, prevent themselves from being 
drowned: or, if breathing by means of gills, they protect themselves from 
-superoxygenation during the low tide. We may further be interested in 
any adaptations, or unique instincts, which make the inhabitants of such a 
locality especially adapted to their environment. 
The following observations on the habits of the insects of the between 
tides zone, were made in the region directly horth of Jones’ bath house 
at the head of Cold Spring Harbor Bay; which is included in the lines 
drawn from 600 E., 200 S., to 200 N., 400 E; and 200 N., 800 E., on map 
of Inner Harbor made by Johnson and York. Many observations were 
made on the extreme outer limit of the Spartina cynosuroides 275 N., 
400 E. The slope of the shore to the west of the boat landing from 
the outer limit of the Spartina to within two feet of the inner limits 
of the Spartina is about 6%. From the latter point to the inner limit of the 
Spartina the slope is more abrupt. The Spartina is here replaced by a short 
(about six inches high), densely matted grass, Juncus Geravdi. This covers 
the entire region around the bath house with the exception of a few pebble- 
covered areas on Which there is a sparse growth of Spergularia Marina. 
(Map 2.) 
The highest tides of the summer, July 8, 9.2 feet; August 3, 8.8 feet; 
submerged the region as far as the bath house. [From July 11 to July 
29 the Spartina area was never entirely submerged, due to the low tides 
and the absence of any strong easterly winds. The observations extended 
from July 1, to August 5, 1915. 
