A phenolic resin plastic sheet (1/8 x 12x30 inches), onto which smaller test 

 specimens were attached and then secured to the bio-racks, was damaged by borers. 

 The damage was confined to the area where the wood panels were secured to the 

 plastic sheet. The borers had attacked the wood first and hod then continued to 

 penetrate into the surface of the plastic sheet. 



Plastic Sheet . A 0.020x4x4-inch white, high-impact styrene sheet which was 

 used as a spacer between the large wood bait piece and the metal bio-rack was dam- 

 aged by borers (Figure 37). 



Glass Microscope Slides. Except for some microbial forms and hydroid growth 

 over the surface of the glass, microscopic examination revealed no visible effects of 

 etching or frosting by microorganisms (Figure 38). Photomicrographs of some of the 

 deep sea microbial forms found on the glass are shown in Figures 39 and 40. 



Figure 37. Borer damage to 20-mil-thick high-impact styrene sheets 

 which were in contact with wood bait piece. 



38 



