Brownish fungi hyphae (without the fruiting bodies) were detected in the wood. 

 An unsuccessful attempt was mode in the laboratory to induce fructification by the 

 fungi for classification purposes. 



Rope Specimens. A heavy growth of slime bacteria was present over the 

 surfaces of cotton and Manila ropes, and a light growth of slime was present over 

 the surfaces of nylon and polypropylene ropes (Figure 17). 



The fibers of cotton rope were decayed considerably by bacterial action, and 

 as a result were easily pulled apart by tweezers (Figure 18). When the cotton rope 

 was handled after it had been dried, the rope fibers crumbled into small pieces. 

 Only a few borers were found on the surface of the cotton rope and none of these 

 had bored into the rope. 



The 1/2-inch-diameter Manila rope specimens were severely damaged by 

 both borers and microorganisms. Borers ranging in size from 1/32-inch to 1/8-inch 

 diameter had completely infested the entire length of the 5-foot-long rope specimens 

 (Figure 19). The rope fibers were severed completely as the borers penetrated deep 

 Into the rope. The slime bacteria were responsible for the decay and deterioration 

 of the fiber materials. 



Examination of the nylon and polypropylene ropes under a stereoscopic 

 microscope showed that the fibers of these ropes were neither severed nor damaged 

 by marine borers. On the contrary, the fibers were In excellent condition 

 (Figure 20). Table 9 compares the breaking strength of rope specimens before and 

 after deep-sea exposure. 



Plastic Specimens . The sections of 3-foot-long solid plastic rods and vinyl 

 tubes recovered after 13 months on the sea floor In 6,800 feet of water are shown 

 In Figure 21 . 



There were numerous deep and shallow borer holes present underneath the 

 area where large wooden bait pieces were fitted over the lower and upper sections 

 of the plastics (Figure 22). It was found that the lower section exposed about 

 0.5 foot above the sediment layer had more borer holes than on the upper sections 

 exposed about 3 feet above the sediment. In other words, the borers were found 

 to be more active near the sediment than 3 feet above the sediment layer. 



The number and size of the borer holes found on the surface of the plastic 

 specimens are presented In the Appendix. 



A vinyl tube (NCEL No. 338) intended for low-temperature use had a heavy 

 bacterial slime growth over the entire tube and over the plastic, rubber, and burlap 

 wrappings. When recovered, the open tube was quite rigid and had decreased In 

 diameter by about 1/8 inch, perhaps because the plastlclzer or some other chemicals 

 used In the tube's formulation may have been lost as a result of bacterial slime 

 activity or other effects of the deep-sea environment. The other three vinyl tubes 

 listed In the Appendix had a light slime growth over the surface; the diameters of 

 these tubes remained unchanged except where marine borers had penetrated the 

 surface of the plastic under the area of the wooden bait pieces. 



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