Ik of the 57 control panels and on 22 of the kk test panels. Bugula 

 nerltina occurred most frequently, tut B. fla"bellata and B. sp. also were 

 identified. One of the test panels was one-third covered. 



d. Annelida (n)n,rine worms ). Serptilid ( Serpula ) tu"beB occurred 

 on 5 of the 57 control panels and on 22 of 'the kk test pajiels, the maximum 

 length recorded being 60 ram after 8 months' sulamergence . Mad. vorm tuhes 

 ( Dasychone ) occurred on 5 of the test panels, the maximum number 

 recorded on any one being 60 tubes. 



e. Arthropoda (crustaceans ). Balanus (barnacles) occurred on 

 25 of the 37 control panels axid on 58 of the kk test panels. They developed 

 on the control pajiels every month of the yesj:* except December, but occurred 

 most frequently from the middle of February to the middle of November. One 

 panel was 75^ covered. The maximum diameter recorded on the control peinels 

 was 12 mm, while that on the test panels was 22 mm after k months' sub- 

 mergence. 



f. Mollusca (nonboring mollusks ). Anomia (jingle-shells) 

 occurred on 2 control panels ajid on 5 test panels; a maximum of kO was 

 recorded on any of the test panels. Maximum diameters recorded were 



6 mm on a control pginel and I5 mm on a test panel after 3 months* sub- 

 mergence. Ostrea (oysters) occurred on 3 of the 57 control panels ajid on 

 20 of the kk test panels; a maximum of 60 was recorded on any of the test 

 panels. Maximum diameters recorded were l4 ram on a control panel and 50 ram 

 on a test panel after 8 months' submergence. 



g. Chorda ta (tunicates ). Tunicates occurred on 8 of the kk 

 test panels, one panel being 259^ covered. 



A26.O5 Summary and Conclusions 



1. Installation . A test board of the panel type installed at the 

 U. S. Naval Operating Base at Trinidad, British West Indies, on August I6, 

 19^i)-, is still being operated. The results of this test have been summarized 

 to the end of 19i|-7. 



2. Test Besults . 



' a. Borers . Teredinidae were very active each year at this 

 location, and the breeding season appears to be more or less continuous. 

 Most of the panels submerged for 8 months, and even a pajiel that was 

 submerged for only k months, were riddled. The attack rated as very heavy. 

 Limnoria also were active throughout the period covered by the test, but 

 the attack rated generally from a trace to slight, although attaining a 

 peak rating of moderate late in 19^5. Pholadidae occurred irregularly, the 

 attack rating slight in 19l^5. 



121 



