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'covered glass cylinder and placed it where it would be covered by the 

 tide. As the tide filled the jar they made no effort to change their posi- 

 tions. Those on the grass blades remained in the same position, as did 

 also those on the ground. The Bdellida? were still alive in the cylinder 

 after it had been submerged by two tides ; i. e., two periods of submergence 

 of five hours each, one period of terrestrial conditions of four hours. 



Lycosa Communis. 

 Although the inner limit of the tidal drift, with its myriads of flies 

 should furnish abundant food for spiders, this is the only species prevalent 

 in the drift covered areas. This is a greyish spider from 4 mm. to 5 mm. 

 in length. They venture out beyond the high tide limit, but will always 

 retreat before the incoming tide. Their long, strong legs, which enable 

 them to run rapidly, make them especially adapted to a region where 

 safety lies in retreat. I often found them running inward on the Juncus 

 when the ground was already covered by the tide. On several I found 

 them isolated on the blades of Spartina grass. When this position was 

 no louger conducive to dryness, they would run rapidly inward over the 

 surface of the water. This is the only insect without wings, frequenting 

 the between tides zone, which retreats before the tide. The Lycosa?. are not 

 only the most rapid runners among the spiders, but can also withstand 

 several hours more submergence than the other spiders of the salt marsh, 

 Grammonata and Clubonia, of course, excepted. 



Many winged insects, beetles, flies, etc., are found on the Spartina 

 during the Ioav tide ; but. although I made no especial study of them, they 

 seem to be only temporary residents. They are never abundant, or even 

 present, immediately upon the retreat of the tide. I never found any sub- 

 merged on the grass when covered by the tide. They are all good fliers 

 and most undoubtedly retreat before the tide. 



On the morning of August 5, when we had the first high tide which 

 covered the outer Spartina area entirely for several weeks, I noticed many 

 Tetragnatha spiders retreating up the Spartina blades because of the rising 

 tide. As the water chased them to the tip of the blade they spun out a long 

 thread which the north wind carried to the higher areas. They ran inward 

 nn the thread. When they accidentally became wetted by the water they 

 became helpless. Should the wind have come from the south, they would 

 have been destroyed. No Tetragnatha were found in areas that had once 



