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reddish brown. These spiders are very abundant in the Spartina region. 

 A short search will reveal a number of them running up and down the 

 Spartina blades or resting head downward on them. 



As the tide comes in, they retreat up the Spartina grass. When 

 the tide has once chased them out on tbe isolated blades of Spartnia (6 to 

 S inches from the tip), they retreat to within about two inches of the tip 

 where they remain head downward until tbe water almost touches them. 

 Then they begin to run wildly up and down the blade, from tip to water, 

 from water to tip, as if they were very much afraid of the water. After 

 doing this a number of times they will calmly walk down the blade under 

 the surface of the water until they come to the pit formed by the union 

 of the stem and the blade. Here tbey remain until the tide retreats. 

 The pit furnishes them protection from aquatic enemies and supplies them 

 with air, for there is always a considerable amount of air left in the pit. 

 That this reaction is due to an effort to secure protection and air, was 

 shown in several experiments. When they were placed on blades of grass 

 weighted to the bottom of the jar which was slowly filled with water, they 

 went down the blades and attempted to crawl under objects at the bottom 

 of the jar. However, to get under some object did not satisfy them, they 

 kept on moving until they came to a bubble of air. Their actions were 

 especially interesting when safety pins were used to weight down the 

 blades. They would walk entirely around the wire part of the pin until 

 they came to the sheatb where there was a quantity of air. Into this they 

 crawled. They always cling tightly to the wire, never attempting to leave 

 it. It is however not essential for them to find a bubble of air. I kept 

 a number of tbem submerged for three days without any noticeable bubbles 

 being present. When they go below the surface, tbey always entangle 

 numerous small air bubbles in their short, dense hairs, which are curved 

 backward seemingly for this special purpose. I performed many experi- 

 ments to compare the resistance of this spider to drowning with that of 

 other species by submerging them in water. In my experiments I used 

 practically all species found farther back on the marsh ; Tetragnatha, 

 Lycosa, Epeira, Attidae, Themsida?. This was the only species, with the 

 exception of the young Clubonia, which could be submerged in water when 

 resting on a grass blade ; i. e., the other species did not hold fast, but tried 

 to escape on the surface of the water. The most striking difference between 

 these spiders when they were placed in small vials whose mouths were 

 covered with cheesecloth and then submerged in a large glass jar of sea 



