-5. Chelura. ChelTira was not otserved in the test pemels imtil 

 July 19^5 i when from 80 to 90 Llmnorla and Chelu3ra tmmels per sq. In. 

 were recorded on all surfaces. It continued to be abundant until the 

 termination of the test. 



A50 . Ok Fouling Agents 



1, Silt . Silt occurred on all the control and test panels except 

 those panels removed on August 22, 19^5* The deposits rated mostly as 

 traces on the control panels and light on the> test panels. 



2, Algae . Algae occurred as traces on 5 of the 15 control panels 

 and as traces to light growths on 7 of the same number of test panels. Both 

 red and green algae were present, but their occurrence was iiregular. 



5. Invertebrate animal phyla . 



a. Coelenterata (hydroids )l Hydroids occurred on 9 of the 15 

 control panels and on 11 of the same number of test panels, the growths 

 rating as traces in all the panels incf ested. 



b. Bryozoa (encrusting ). Two colonies of an encrusting Bryozoa 

 were recorded on one of the test panels. 



c. Annelida (annelid worms ). Serpulld ( Serpula ) tubes occurred 

 more of leas abundantly on 8 of the 15 control peinels. No worms developed on 

 any of the panels submerged between January I7 and June 25, 19^5- Tli© maxi- 

 mum length recorded on the control panels was 12 mm. However, Serpula 

 developed from a few to abiondant on all test panels, attaining lengths from 

 10 mm to 80 mm. 



d. Arthropoda (cnastaceans ). Balanus (beoTaacles) occurred only 

 on the last k of the 15 control panels submerged for periods of a month each 

 from May 22 to August 22, 19^5. The maximum diameters recorded on any of 

 these panels was 12 mm, and the number on any panel did not exceed 25. They 

 occxirred only in small numbers on k of the 15 test panels, where a TnaTimurn 

 diameter of 8 mm was attained on one panel submerged for 8 months. Their 

 occurrence appears to have been merely sporadic. 



A50 . 05 Summary and Conclusions 



1. I nstall ation . A test board of the panel type was operated at the 

 U. S. KiavEil Operating Base at Palermo, Sicily, Italy, from August 21, 19kk 

 until its discontinuance on September 2k, 19^5 ^ to determine the identity 

 and prevalence of marine borers and fouling organisms occurring at this 

 location. 



155 



