and test series except on 2 of the former. The deposits ranged from 

 traces to light on the panels of the control series, and froiii moderate 

 to heavy, and occasionally oily, on the panels of the test series. 



2. Invert e"brate animal phyla . 



a. Coelenterata (hydroids ). Hydroids occurred as traces 

 or light growths on 12 of the control panels, althcpugh no f03rms occurred 

 on any of the k removed after Octoher 18, 19^5. They occurred on all 

 of the 19 of the test panels, the growths "being mostly moderate or heavy. 



"b. Arthropoda (crustaceans ). Barnacles occurred on only 2 

 of the 19 control panels and on 6 of the same number of test panels. 

 One of the test panels was 2^f> covered. Maximum diameters of 4 mm were 

 recorded on the. control panels ajid 12 ram on a test panel which had 

 been submerged for 8 months . Amphipods (mostly Corophium ) occuarred on 

 10 control panels and on l6 of the 19 test panels, frequently "being 

 numerous, particularly on ihe test panels. 



A59 • 05 Summary and Conclusions 



1. Installation . A test "board of the panel type was operated 

 at the U. S. Naval^<Stat±on at Astoria, Oregon, from July 18, 19^^ 

 until its discontinuance on Fe"bruary 18, 19^6, to determine, the identity 

 and prevalence of marine borers and fouling organisms occurring at this 

 location, 



2. Test Eesults . 



a. Borers . There was no evidence whatever of activity of 

 marine borers during the approximately 1^-year period covered by the 

 test. The daily variation of the water from saline to practically 

 fresh would preclude the possibility of either Teredinidae or Limnoria 

 becoming established at this location. 



b. Fouling Organisms . Silt and invertebrate animals 

 belonging to 2 phyla contributed' to the -fouling of the pemels. The 

 invertebrate animals comprised hydroids, and barnacles and amphipods, the 

 latter being largely Corophium . Of these organisms, the hydroids 

 occurred with considerable frequency, Corophium occurred with less- 

 frequency, and barnacles occurred with still less frequency. 



175 



